# Pool, Spa & Sauna Accessories A pool, spa or sauna accessory's category decides which spec matters, not its price: a cleaner by how it gets suction and what it reaches, a cover by its ASTM safety class or bubble thickness, a water device by whether it separates free from combined chlorine, and a sauna rock by its mineral. ## How it works A cleaning tool moves debris to a filter: a robot scrubs on its own battery or low-voltage motor, a pressure-side unit is driven by return-line pressure (often through a booster pump) into its own catch bag, a suction-side unit is towed by the main pump's suction, and a manual brush or net just needs a person on a pole. A cover works as a barrier: a safety cover is load- and opening-tested to ASTM F1346 to resist a fall, while a solar or winter cover only traps heat or keeps out debris and carries no such rating. A water-chemistry device reads the water (strip, drop kit, or digital) or doses it (floating feeder, inline feeder, or salt generator). A sauna accessory works with dry radiant heat: loose rock holds the heater's heat and releases steam when water is ladled onto it. ## How an expert narrows the choice ```mermaid timeline section 1 · What kind of accessory cleaning_tool : ask How the cleaner moves : skip Cover safety class, How water is tested, How sanitizer gets dosed, Sauna rock mineral cover : ask Cover safety class : skip How the cleaner moves, How water is tested, How sanitizer gets dosed, Sauna rock mineral water_chemistry_device : ask How water is tested, How sanitizer gets dosed : skip How the cleaner moves, Cover safety class, Sauna rock mineral sauna_accessory : ask Which sauna accessory : skip How the cleaner moves, Cover safety class, How water is tested, How sanitizer gets dosed section 2 · How the cleaner moves robotic : ask Where debris gets caught, What it actually cleans, What it needs to run, How it finds its way around : skip Brush/net material pressure_side : ask Where debris gets caught, What it actually cleans, What it needs to run : skip Brush/net material suction_side : ask Where debris gets caught, What it actually cleans : skip Brush/net material, What it needs to run manual_pole_tool : ask Brush/net material : skip Where debris gets caught, What it actually cleans, What it needs to run section 3 · Cover safety class power_safety_cover : ask Mesh or solid fabric : skip Solar cover thickness, Winter cover fabric weight manual_safety_cover : ask Mesh or solid fabric : skip Solar cover thickness, Winter cover fabric weight other_cover_not_rated : ask Solar cover thickness, Winter cover fabric weight : skip Mesh or solid fabric section 4 · How water is tested Want the fastest check, or the most accurate chlorine reading? ``` 1. **What kind of accessory.** A cleaner, a cover, a water tester/feeder, or sauna rocks? Each job has its own spec sheet built on a different decision tree; asking this first routes straight to the right facets instead of asking about mil thickness on a water tester. If cleaning_tool: ask How the cleaner moves; skip Cover safety class, How water is tested, How sanitizer gets dosed, Sauna rock mineral. If cover: ask Cover safety class; skip How the cleaner moves, How water is tested, How sanitizer gets dosed, Sauna rock mineral. If water_chemistry_device: ask How water is tested, How sanitizer gets dosed; skip How the cleaner moves, Cover safety class, Sauna rock mineral. If sauna_accessory: ask Which sauna accessory; skip How the cleaner moves, Cover safety class, How water is tested, How sanitizer gets dosed. Skip if already known: a query that already names a cleaner, cover, test kit, feeder, or sauna accessory. 2. **How the cleaner moves.** A self-driving robot, pressure or suction, or a manual pole tool? Drive type sets install needs and coverage: robots are independent, pressure/suction reuse existing plumbing, manual needs a person at the pole every time. If robotic: ask Where debris gets caught, What it actually cleans, What it needs to run, How it finds its way around; skip Brush/net material. If pressure_side: ask Where debris gets caught, What it actually cleans, What it needs to run; skip Brush/net material. If suction_side: ask Where debris gets caught, What it actually cleans; skip Brush/net material, What it needs to run. If manual_pole_tool: ask Brush/net material; skip Where debris gets caught, What it actually cleans, What it needs to run. Skip if already known: an earlier answer already naming robotic, pressure, suction, or manual. 3. **Cover safety class.** A safety cover rated to hold weight, or a winter/solar cover? Only Power and Manual Safety Covers are load- and opening-tested under ASTM F1346; a winter or solar cover carries no such rating no matter how heavy it feels. If power_safety_cover: ask Mesh or solid fabric; skip Solar cover thickness, Winter cover fabric weight. If manual_safety_cover: ask Mesh or solid fabric; skip Solar cover thickness, Winter cover fabric weight. If other_cover_not_rated: ask Solar cover thickness, Winter cover fabric weight; skip Mesh or solid fabric. Skip if already known: an earlier answer naming a safety cover, winter cover, or solar cover. 4. **How water is tested.** Want the fastest check, or the most accurate chlorine reading? Accuracy and what the method tells apart both change: strips are fastest but least precise, FAS-DPD titration is most precise at separating free from combined chlorine. Skip if already known: an earlier answer naming strips, a drop kit, FAS-DPD, or a digital tester. ## What to surface ### What kind of accessory Which job the item does: removing debris and scrubbing, covering the water or air gap, testing or dosing water chemistry, or heating rocks in a sauna. Each job has its own spec sheet: a cleaner is judged by how it gets suction and what it covers, a cover by its ASTM safety class or mil thickness, a tester or feeder by what it can measure or dose, and a sauna rock by its mineral. Asking this first stops the wrong facet set from loading. [14] [1] [11] [19] Values: cleaning_tool, cover, water_chemistry_device, sauna_accessory. Question to ask: A cleaner, a cover, a water tester/feeder, or sauna rocks? Used as: top-level split, filter. Data: derived from listing fields, backfill cost low. Look for it as: Derive from the product title and category breadcrumb (vacuum/robot/skimmer, cover, test kit/feeder/chlorinator, sauna stones/bucket). Title and breadcrumb keyword match covers nearly all listings. ### How the cleaner moves How the cleaner gets its suction or motion: its own motor and brushes (robotic), the pool's return-line pressure through a booster pump (pressure-side), the pool's main pump and filter through a suction line (suction-side), or a human pushing a pole (manual). Drive type sets the cost, the install, and what else has to already be true about the pool: a robot needs only a GFCI outlet nearby, or no outlet at all if battery-cordless; a pressure-side cleaner needs a return jet and usually its own booster pump; a suction-side cleaner runs off the existing pump but adds to its load; a manual tool needs a person at the pole every time. [14] [15] Values: robotic, pressure_side, suction_side, manual_pole_tool. Question to ask: A self-driving robot, pressure or suction, or a manual pole tool? Used as: top-level split, filter. Data: on the listing, backfill cost low. Look for it as: Almost always in the title ('Robotic Pool Cleaner', 'Pressure Side Cleaner', 'Suction Vacuum', 'Telescopic Pole Skimmer'). Title keyword match; 'cordless'/'battery' in the title marks the robotic sub-type that needs no outlet at all. Chart: position on an install-complexity axis, manual lowest, pressure-side with a booster pump highest. ### How water is tested How the water sample's chemistry gets read: a dip-and-match color strip, a liquid drop-count kit, a titration kit using the FAS-DPD reagent, or a digital photometer. Accuracy and what the method can tell apart both change: strips are fast and cheap but low-to-moderate accuracy and many only estimate total chlorine; a standard drop kit gets free chlorine directly and total by subtraction; FAS-DPD titration reads free and combined chlorine directly in 0.2 ppm steps, the resolution needed to catch a combined-chlorine problem early; digital photometers remove color-matching guesswork at a higher cost per test. [10] [11] Values: test_strips, dpd_drop_kit, fas_dpd_titration, digital_photometer. Question to ask: Want the fastest check, or the most accurate chlorine reading? Used as: top-level split, filter. Data: on the listing, backfill cost low. Look for it as: Usually stated in the title ('Test Strips', 'FAS-DPD Test Kit', 'Digital Pool Tester'). Title keyword match; Taylor-style kit numbers (e.g. K-2006) in the title identify FAS-DPD kits specifically. Chart: position on an accuracy axis, strips lowest, FAS-DPD and digital highest. ### Cover safety class Which of ASTM F1346's three label classes the cover carries: Power Safety Cover (opens and closes with a motor), Manual Safety Cover (placed by hand but tested to the same load and opening standard), or Other Cover (a winter, solar, or debris cover with no safety rating). Only Power and Manual Safety Covers are tested to hold a child's weight and stop a small body passing through an opening; a winter or solar cover is labeled 'not a safety cover' under the same standard and should never be relied on to stop a fall. The class is on the cover's own sewn or riveted label. [1] [2] [3] Values: power_safety_cover, manual_safety_cover, other_cover_not_rated. Question to ask: A safety cover rated to hold weight, or a winter/solar cover? Used as: top-level split, filter. Data: on the listing, backfill cost medium. Look for it as: Safety covers name the class on their label per ASTM F1346 clause 8.12; listings usually say 'ASTM-rated safety cover' vs plain 'winter cover' or 'solar cover'. Title keyword match catches most listings; the exact PSC vs MSC split needs the description or spec label. ### How sanitizer gets dosed How sanitizer gets into the water on an ongoing basis: a floating tablet feeder, an inline automatic feeder plumbed after the filter, or a salt chlorine generator that makes chlorine electrolytically from dissolved salt. A floating feeder is cheap but dissolves tablets at the mercy of water flow and can get stuck in corners; an inline feeder gives a dial-adjustable, consistent dose but has to be plumbed into the equipment pad; a salt generator removes manual dosing almost entirely but costs more upfront and needs the pool's salt level maintained. [12] [13] Values: floating_feeder, inline_automatic_feeder, salt_chlorine_generator. Question to ask: Drop in tablets, have it dial-dosed, or make chlorine from salt? Used as: filter, shown on the card. Data: on the listing, backfill cost low. Look for it as: Stated in the title/category ('Floating Chlorinator', 'Automatic Chlorine Feeder', 'Salt Chlorine Generator'). Title/category keyword match. ### Which sauna accessory Which sauna accessory this is: the heater's loose stone bed, the bucket and ladle used to pour water onto hot stones for steam, or a thermometer/hygrometer that reads the room's heat and humidity. Each is judged on a different thing: stones on their mineral and the heater manual's size and weight spec, a bucket and ladle on material and liner, and a thermometer/hygrometer on whether it also reads humidity, not just heat. [19] Values: heater_stones, bucket_and_ladle, thermometer_hygrometer. Question to ask: Stones, a bucket and ladle, or a heat/humidity gauge? Used as: filter, shown on the card. Data: derived from listing fields, backfill cost low. Look for it as: Derive from the product title/category ('sauna stones', 'bucket and ladle', 'sauna thermometer'). Title keyword match covers nearly all listings. ### Brush/net material What a manual cleaning tool's working surface is made of: nylon bristle, stainless-steel bristle, a nylon/steel combo, or open leaf-rake mesh. Only polyester/nylon bristle is safe on vinyl, fiberglass and resin surfaces; stainless-steel bristle can scratch those finishes and belongs on concrete or plaster instead. A leaf rake's mesh is for skimming floating debris, not scrubbing. [17] [18] Values: nylon_bristle, stainless_steel_bristle, combo_bristle, leaf_rake_mesh. Question to ask: What's the pool surface: vinyl/fiberglass, or plaster/concrete? Used as: filter, shown on the card. Data: on the listing, backfill cost low. Look for it as: Stated in the title ('Stainless Steel Pool Brush', 'Nylon Bristle Brush', 'Leaf Rake'). Title keyword match; default to nylon when unstated since it is the surface-safe default. ### Solar cover thickness The solar (bubble) cover's material thickness, measured in mil (one mil equals 0.001 inch). Thickness trades handling ease for durability and heat retention: 12 mil is the common residential middle ground, light enough to pull on and off by hand, while 16 mil holds its bubble structure and heat-trapping ability longest but is heavy enough that a reel system becomes worth buying. [6] [7] Range: 12 to 16 mil. Question to ask: Lightest cover to handle, or most durable and heat-trapping? Used as: filter, shown on the card. Data: on the listing, backfill cost low. Look for it as: Mil thickness is usually stated directly in the title or a spec bullet (e.g. '12 Mil Solar Cover'). Direct numeric parse from title/spec bullet; default to 12 mil, the common residential thickness, when absent. Chart: position on a thickness/durability axis, 12 mil to 16 mil. ### Sauna rock mineral What the sauna's heater rocks are made of: dense volcanic olivine diabase, denser peridotite, or another stone not meant for heater use. Olivine diabase is the standard rock shipped with most heaters and heats up quickly; peridotite is denser and more resistant to the thermal shock of repeated water ladling, which is why some buyers upgrade to it; porous landscaping or BBQ lava rock is not sauna-rated and can crack or crumble under that same thermal shock. [19] [20] Values: olivine_diabase, peridotite, other_not_sauna_rated. Question to ask: Fine with the standard rock, or one built for years of ladling? Used as: filter, shown on the card. Data: on the listing, backfill cost low. Look for it as: Usually named directly in the title ('Olivine Diabase Sauna Stones', 'Peridotite Sauna Rocks'). Title keyword match; default to olivine diabase when unstated since it ships with most heaters. ### Bucket & ladle material What the sauna bucket and ladle are made of: timber with an inner plastic liner, metal such as aluminium, steel or copper, or molded plastic. A wood bucket is the traditional look, but bare timber swells, leaks or eventually cracks from repeated water contact, so most wood buckets ship with a fitted plastic liner that protects the wood and simplifies cleaning; metal and molded-plastic buckets skip the liner question entirely since neither absorbs water the way timber does. [21] [22] Values: wood_with_plastic_liner, metal, molded_plastic. Question to ask: Wood look, metal, or plastic bucket and ladle? Used as: filter, shown on the card. Data: on the listing, backfill cost medium. Look for it as: Material is usually in the title ('Alder Sauna Bucket', 'Anodised Aluminium Sauna Pail'); whether a wood bucket has a liner usually needs the spec table. Title keyword match for material; default to wood_with_plastic_liner, the common modern construction, when a wood bucket's liner isn't stated. ### Thermometer or combined hygrometer Whether the gauge reads only the sauna's temperature, or temperature and humidity together on one face. A thermometer-only gauge tells you the room is hot enough; a combined thermometer/hygrometer also reads humidity, which matters for how steamy the room feels after water is ladled onto the rocks, a comfort factor temperature alone doesn't capture. [23] [24] Values: thermometer_only, combined_thermometer_hygrometer. Question to ask: Just temperature, or humidity too? Used as: filter, shown on the card. Data: on the listing, backfill cost low. Look for it as: Stated directly in the title/type field ('Sauna Thermometer' vs 'Sauna Thermometer & Hygrometer'). Title keyword match on presence/absence of 'hygrometer'. ### What it actually cleans Which pool surfaces the cleaner reaches: just the floor, floor and walls, or floor, walls and the waterline scum line. Suction and most pressure-side cleaners reliably clean only the floor; wall-climbing is an added feature on some pressure and most robotic cleaners, and only a subset of those also scrub the waterline where body-oil scum collects. [14] Values: floor_only, floor_and_walls, floor_walls_and_waterline. Question to ask: Just the floor, or walls and the waterline too? Used as: filter, shown on the card. Data: needs research, backfill cost medium. Look for it as: Often a bullet ('climbs walls', 'cleans waterline') rather than a dedicated field. Needs a description/bullet scan; title alone rarely says it. Chart: stacked coverage bar, floor to waterline. ### Mesh or solid fabric For a safety cover, whether the fabric is a woven mesh that water passes through, or a solid vinyl panel that needs its own drain panel or pump to clear rainwater. Mesh drains on its own and needs no pump, but even a tight weave only blocks about 99% of UV, which can feed algae if sanitizer runs low over winter; a fully solid cover blocks sunlight entirely but pools standing water on its center panel unless it ships with a drain panel or cover pump. [4] [5] Values: standard_mesh, tight_weave_mesh, solid_with_drain_panel, solid_with_pump. Question to ask: OK with some light getting through if it self-drains, or fully dark? Used as: filter, shown on the card. Data: on the listing, backfill cost low. Look for it as: Usually in the title or bullets ('mesh safety cover', 'solid safety cover with drain panel'). Title keyword match on mesh/solid plus any drain-panel mention. Chart: position on a UV-blocking axis, mesh lowest, solid highest. ### What it needs to run What the cleaner needs to operate: its own battery, a low-voltage cord into a GFCI outlet, the pool's existing pump with no extra power draw, or a separate booster pump. A battery-cordless robot needs no outlet near the pool at all; a corded robot needs a GFCI outlet within cord reach; a suction-side cleaner adds no new equipment; a pressure-side cleaner often needs its own booster pump installed, which is an extra purchase and an extra point of failure. [14] [15] Values: battery_cordless, corded_low_voltage_gfci, runs_off_existing_pump, dedicated_booster_pump. Question to ask: Fine with a battery, or does it plug in or tap plumbing? Used as: filter, shown on the card. Data: on the listing, backfill cost low. Look for it as: 'Cordless'/'battery' or 'booster pump required' usually appears in the title or first bullet. Keyword match on cleaner_drive_type plus 'cordless'/'booster pump' in the title or bullets. ### How it finds its way around Whether the robotic cleaner moves in a random bump-and-turn pattern, or scans the pool first to plan a systematic, mapped path. A random-pattern cleaner can miss spots or re-cover the same area within one cycle; a cleaner that scans the pool and plans its path instead of relying on random movement is more likely to reach the whole floor (and walls, on climbing models) in a single run. [14] [16] Values: random_pattern, mapped_path. Question to ask: Fine with random movement, or want it to map the pool? Used as: filter, shown on the card. Data: on the listing, backfill cost medium. Look for it as: Higher-end models say 'smart navigation', 'mapping', or 'scans the pool' in the title or bullets; otherwise assume random. Needs a bullet/description scan; default to random_pattern for basic robotic models when unstated. ### Winter cover fabric weight The winter (solid tarp) cover's vinyl fabric weight, measured in ounces per square yard. Heavier fabric sheds ice and snow load and resists punctures and cold-cracking better: 8 oz sits at the light, budget end for mild climates, while 18-20 oz cold-crack-resistant vinyl is the recommendation for heavy snow and sub-zero winters. [8] [9] Range: 8 to 20 oz/sq yd. Question to ask: Mild winters, or heavy snow and hard freezes where you live? Used as: filter, shown on the card. Data: needs research, backfill cost medium. Look for it as: Rarely on big-box/marketplace listing titles or bullets; the oz/sq-yd number mostly appears on brand-style spec pages, not ordinary retail listings. Needs the spec table on a brand spec page, not just the title; default to mid-weight (about 12-15 oz) when missing. Chart: position on a durability axis, 8 oz to 20 oz. ### Where debris gets caught Where the debris the cleaner picks up actually gets caught: a cartridge or bag built into the cleaner, a bag clipped onto the return line, the pool's own skimmer basket and main filter, or nothing for a manual tool. A robotic or pressure-side cleaner with its own catch bag keeps fine debris out of the pool's main filter, so that filter gets cleaned less often; a suction-side cleaner sends everything it picks up straight through the main pump and filter, adding to that filter's load on every run. [14] Values: onboard_cartridge_or_bag, clip_on_bag_return_line, pool_main_filter, none_manual. Used as: filter, shown on the card. Data: needs research, backfill cost low. Look for it as: Not usually a listing field on its own; derive from cleaner_drive_type. Derive directly from cleaner_drive_type; no separate lookup needed. ### What it can tell apart What the test can actually distinguish: total chlorine only, free and total chlorine (with combined found by subtracting), or free and combined chlorine read directly. A reading of 'chlorine is fine' from a total-only test can hide a sanitizer problem, because most of that number can be combined chlorine rather than free chlorine actually available to sanitize; only a method that separates the two tells a buyer whether to shock the pool. [11] [10] Values: total_chlorine_only, free_and_total_by_subtraction, free_and_combined_direct. Used as: filter, shown on the card. Data: needs research, backfill cost low. Look for it as: Not a listing field; derive from test_method (strips/OTO = total only, drop kit = free+total, FAS-DPD = free+combined direct). Derive directly from test_method; no separate lookup needed. ## What you give up - A suction or pressure-side cleaner reuses equipment the pool already has, but a robot is the type most likely to reach the waterline and walls on its own motor, at a higher price and its own power needs. [14] [15] Board branch: "More coverage, more equipment to own". - A solid safety cover blocks sunlight entirely, which is why pools under them are usually cleaner in spring, but standing water collects on the panel after rain; mesh drains itself but lets enough UV through to feed algae if sanitizer runs low. [4] [5] Board branch: "Less algae, more standing water to manage". ## Words you will meet - **Free chlorine (FC)**. The chlorine still active and available to sanitize the water right now. - **Combined chlorine (CC)**. Chlorine that has already reacted with contaminants and no longer sanitizes well; also called chloramines. - **FAS-DPD**. A drop-by-drop titration test that reads free and combined chlorine directly, in 0.2 ppm steps. - **ASTM F1346**. The standard a pool/spa safety cover is tested and labeled against for load, openings, and drainage. - **Mil**. A thickness unit equal to 0.001 inch, used for solar (bubble) pool covers. - **Booster pump**. An extra pump some pressure-side cleaners need to get enough water pressure to move. - **Return-line pressure**. Water pressure on the pipe that feeds water back into the pool, used to drive a pressure-side cleaner. - **Suction line**. The pipe that pulls water (and a suction-side cleaner) toward the pool's main pump and filter. - **Photometer**. A small device that reads a water sample's color electronically instead of by eye, for a more precise chlorine reading. - **GFCI outlet**. A shock-protected outlet required near pool equipment that corded electric cleaners plug into. - **Olivine diabase**. A dense volcanic rock that is the standard stone shipped with most sauna heaters. - **Peridotite**. A denser volcanic rock than olivine diabase, chosen for better resistance to repeated water-ladling. - **Salt chlorine generator**. A device that makes chlorine from dissolved pool salt through electrolysis, instead of adding tablets. - **Waterline**. The ring at the pool's water surface where body oil and sunscreen leave a scum line. - **Safety cover (PSC/MSC)**. A Power or Manual Safety Cover: the only two ASTM F1346 classes actually tested to hold weight. ## Where we made a call - FAS-DPD titration is the most accurate common home chlorine test; strips and OTO are least accurate. (confidence high). Corroborated by an enthusiast-community kit comparison and an independent testing-method comparison; both rank FAS-DPD above drop/DPD above strips/OTO. [10] [11] ## References 1. [Safety Covers and Labeling Requirements for All Covers for Swimming Pools, Spas and Hot Tubs (ASTM F1346-23 text)](https://coverstarcentral.com/images/website_custom_table_file.php?table=pdfs&id=6&field=internal_pdf) (standards body). Supports: Defines Power Safety Cover, Manual Safety Cover and Other Covers as the three label classes; Static load test is 485 lb over 8 ft wide/diameter, 275 lb at 8 ft or under. 2. [Is My Pool Cover a Safety Cover?](https://www.activepoolsupply.com/pages/is-my-pool-cover-a-safety-cover) (primer). Supports: ASTM F1346 sorts covers into three label classes; only two are safety covers; Static load test is 485 lb (over 8 ft) or 275 lb (8 ft or under), per clause 8.12 labeling. 3. [ASTM Standard F1346-91 Compliant Pool Safety Covers](https://katchakid.com/astm-standard-f1346-91-compliant-pool-safety-covers/) (primer). Supports: Cover must drain substantially all standing water within 30 minutes of rain ending; Static load test is 485 lb (over 8 ft) or 275 lb (8 ft or under). 4. [Mesh vs. Solid Safety Pool Covers - Which is Best?](https://www.intheswim.com/blog/mesh-vs-solid-safety-pool-covers-which-is-best.html) (specialist review). Supports: Mesh drains itself via a panel or pump but still lets in some fine sediment and sunlight; Solid covers minimize sunlight and particles but need a drain panel or cover pump. 5. [Which Type of Safety Cover Is Right for My Swimming Pool?](https://blog.royalswimmingpools.com/which-type-of-safety-cover-is-right-for-my-swimming-pool) (specialist review). Supports: A tight-weave mesh safety cover blocks about 99% of UV; Solid safety covers block sunlight entirely, keeping pool water algae-free over winter. 6. [Best Pool Solar Cover Thickness for Heat Retention and Savings](https://backyardalpha.com/best-pool-solar-cover-thickness/) (specialist review). Supports: 16 mil solar covers are positioned for stronger heat retention and durability. 7. [Best Solar Pool Cover 12 Mil vs 16 Mil: A Practical Comparison](https://patchpilotry.com/best-solar-pool-cover-12-mil-vs-16-mil/) (specialist review). Supports: Compares 12 mil and 16 mil solar covers on heat retention and durability; 16 mil covers suit cooler climates and larger or deeper pools. 8. [Winter Pool Cover](https://poolguardusa.com/winter-pool-cover/) (spec sheet). Supports: Winter pool cover vinyl weighs 8 to 20 oz per square yard depending on thickness. 9. [Tarp Material Weight & Thickness Chart](https://www.heavydutytarps.com/material-weights) (spec sheet). Supports: Vinyl and mesh tarp material weight/thickness chart runs up to 22 oz per square yard. 10. [Swimming Pool Test Kits Compared / FAS-DPD glossary](https://www.troublefreepool.com/blog/2019/01/18/test-kits-compared/) (enthusiast community). Supports: FAS-DPD is a drop-count titration reading free and combined chlorine to 0.2 ppm; Test strips and the OTO test are less accurate than a liquid drop kit. 11. [Pool Water Testing Methods: Strips vs DPD vs Digital](https://www.poolfounder.com/pool-water-testing-methods-comparison) (specialist review). Supports: OTO and many test strips measure total chlorine only, not free or combined separately; FAS-DPD titration reads free and combined chlorine directly at 0.2 ppm resolution. 12. [The Three Types of Pool Chlorinators](https://lesliespool.com/blog/the-three-types-of-pool-chlorinators.html) (spec sheet). Supports: Three chlorinator types for pools: automatic (inline), salt, and floating tablet feeders. 13. [Chemical Feeders eGuide](https://www.intheswim.com/eguides/chemical-feeders.html) (spec sheet). Supports: Floating chlorinators are the inexpensive, simplest tablet-feeder option for any pool. 14. [Types of Pool Cleaners: Robotic vs. Pressure vs. Suction](https://poolresearch.com/pool-vacuums/) (specialist review). Supports: Robotic, pressure-side and suction-side cleaners differ in power source and coverage; Pressure-side cleaners require a booster pump on the return line; Suction-side cleaners move randomly around the pool floor; some robotic cleaners have software that maps the pool instead. 15. [Dolphin Robotic Pool Cleaners](https://www.maytronics.com/us/robotic-pool-cleaners) (spec sheet). Supports: Lists cordless (battery) robotic cleaners as a distinct product line from corded models. 16. [The Best Robotic Pool Cleaners in 2026](https://www.swimuniversity.com/robotic-pool-cleaners/) (specialist review). Supports: A higher-end robotic cleaner scans the pool to optimize its path, instead of relying on random patterns. 17. [Pool Brushing (Further Reading wiki)](https://www.troublefreepool.com/wiki/index.php?title=Pool_Brushing) (enthusiast community). Supports: Use only nylon/polyester brushes on vinyl, fiberglass and resin pools, not stainless steel; Stainless steel wire bristles are for concrete/plaster, not vinyl, fiberglass or resin. 18. [Vinyl, Concrete, or Fiberglass: Which Pool Brush Is Right?](https://poolpartstogo.com/blogs/articles/which-pool-brush-is-right-for-you) (specialist review). Supports: Matches brush bristle material (nylon, stainless, combo) to pool surface to avoid damage. 19. [Sauna Stones Guide](https://thermalfinn.com/sauna-heaters/sauna-stones-guide-v2/) (primer). Supports: Olivine diabase and peridotite are the sauna-approved heater stone types; HUUM DROP heater spec: 55 kg of stones in a 5-10 cm size range. 20. [Choosing The Best Rocks For Sauna: A Complete Guide](https://www.steamandsaunaexperts.com/blog/best-rocks-for-sauna) (specialist review). Supports: Peridotite is a dense volcanic rock chosen for heat retention and thermal-shock resistance; Avoid porous lava rocks sold for BBQ/landscaping; they can crack or crumble. 21. [Sauna Buckets & Ladles](https://finnmarksauna.com/collections/sauna-buckets-pails) (retail listing). Supports: Sauna buckets and ladles collection features wooden, copper, plastic, and metal designs. 22. [4 Living Sauna Bucket Alder With Rope Handle 4 Litre](https://finnmarksauna.com/products/4-living-sauna-bucket-alder-with-rope-handle-4-litre) (retail listing). Supports: Heat-treated alder bucket's spec table lists a 'plastic liner fitted' that protects the timber from standing water. 23. [4 Living Sauna Thermometer Black](https://finnmarksauna.com/products/4-living-sauna-thermometer-black) (retail listing). Supports: Spec table lists Type as 'Sauna thermometer' with no hygrometer/humidity function. 24. [4 Living Sauna Thermometer Hygrometer Heat Treated Alder](https://finnmarksauna.com/products/4-living-sauna-thermometer-hygrometer-heat-treated-alder) (retail listing). Supports: Spec table lists Type as 'Combined sauna thermometer and hygrometer', reading both temperature and humidity.