Buy in this order
The order matters more than the list, because early purchases change what later ones need to be. Nearly every expensive pool mistake is a step taken out of sequence — a heater sized before anyone measured the pool, a chlorinator bought to solve a problem that was really a testing problem.
- A proper test kit. Before anything. Every other decision on this page depends on numbers, and the numbers have to be right — a kit that can't read chlorine above 5 ppm or can't test CYA will actively mislead you. This is a $25–90 purchase that decides whether the next $3,000 is spent well.
- The manual tools. Telescopic pole, skimmer net, brush, vacuum head and hose. Under $150 for the set, and a brush is the single most underrated item in pool care — algae that gets brushed off a wall dies in the water, algae that doesn't gets a protective film and survives your chlorine.
- A cover. Before any heating decision, because it changes the answer to all of them. It cuts evaporation, which is where most of a pool's heat and water goes, and it does it for about a fiftieth of what a heater costs.
- Whatever your actual problem is. Now — not before — buy against a specific complaint. Water goes cloudy in August? That's usually chemistry or filtration, not a purchase. Sick of carrying chlorine jugs? Salt system. Sick of vacuuming? Robot. Pool too cold in May? Now price a heater, with the cover already on and the numbers already known.
On our reference pool — a 15 × 30, gas heated — a solar cover costing under $250 keeps about $1,533 of gas and 9,600 gallons of water in the pool over a season. Nothing else here comes close to that return, and it's the item most often skipped because it's the least interesting. Check it against your own pool and rates in the cover savings calculator.
What it costs to own, not just to buy
Retailer lists stop at the price tag, which is the smaller number for anything with a motor in it. A single-speed pump costs a few hundred dollars and then quietly spends that again every season. Below, the purchase price sits next to what our engines say the thing actually costs to run — worked for a 15 × 30 pool (450 ft², about 16,000 gallons) on a seven-month season at $0.17/kWh and $1.50/therm:
| Item | Typical price | What it costs — or saves — to run | Size it with |
|---|---|---|---|
| Test kit | $25–90 | About $20 a year in reagent refills | — |
| Solar cover + reel | $50–250, plus $100–300 for the reel | Saves $1,533 of gas and 9,600 gallons of water a season | Cover savings |
| Single-speed pump (what you probably have) | $300–700 | $550 a season at 8 h/day | Pump electricity cost |
| Variable-speed pump | $700–1,500 installed | $117 a season for the same water — $433 saved | Variable-speed savings |
| Gas heater | $2,000–5,000 | $450 a month covered, $1,081 uncovered | Heating cost |
| Heat pump | $3,500–8,000 | $282 a month covered | Heater sizing |
| Salt chlorine generator | $800–2,000 | Salt is cheap; the cell is $400–900 every 3–7 years | Salt cell sizing |
| Robotic cleaner | $500–1,600 | A few dollars a season in power; belts and brushes as they wear | — |
Running costs computed by the same engine behind our calculators; prices are 2025–26 US ranges and move faster than the math does. The heating rows assume a 15 °F rise above the air — yours depends on your climate and target, which is what the calculators are for.
Two things fall out of that table. The pump is the biggest recurring cost most pool owners have, and the variable-speed upgrade pays for itself in two to three seasons at these rates — the rare case where the expensive option is the cheap one. The heater is in a different league entirely, which is why the cover belongs above it in the buying order rather than below.
Filters: the spec nobody puts on the box
Your filter came with the pool and you'll probably never choose one — until it fails, and then the choice matters more than the price difference suggests. All three types clean water; they differ in how fine a particle they can catch, which decides whether a cloudy pool clears in a day or never quite does.
| Type | Catches down to | Upkeep | Suits |
|---|---|---|---|
| Sand | ~20–40 microns | Backwash when pressure rises; change sand every 5–7 years | Simplest to live with, cheapest to run, worst at fine haze. A cup of DE through the skimmer sharpens it considerably |
| Cartridge | ~10–20 microns | Hose it down a few times a season; replace elements every 2–4 years | The sweet spot for most residential pools, and no backwashing means no water wasted |
| DE | ~3–5 microns | Backwash and recharge with fresh powder; strip and clean annually | The clearest water available, at the cost of the most handling. Some regions restrict DE discharge |
Approximate media ratings. For scale, the particles that make water look cloudy are mostly 0.5–5 microns — which is why filter type is the hidden variable in half the "why won't my pool clear" questions.
Sizing rule: oversize it. A filter rated well above your pool's flow runs at lower pressure, catches more, and goes longer between cleanings. Unlike a pump, there's no efficiency penalty for buying big — the only cost is the purchase.
The chemicals actually worth stocking
A pool store aisle has perhaps sixty products in it. A well-run pool uses about five, and four of them are cheap commodity chemicals sold under names that make them sound like pool products:
| Keep on hand | What it's for | Also sold as | Dose it with |
|---|---|---|---|
| Liquid chlorine (10–12.5%) | The daily sanitizer — adds nothing but chlorine and salt | Sodium hypochlorite; household bleach is the same thing, weaker | Chlorine dosing |
| Muriatic acid | Bringing pH down, which almost every pool needs regularly | Hydrochloric acid, 31.45% or a safer 14.5% | pH adjustment |
| Baking soda | Raising alkalinity | Sold as "alkalinity increaser" at several times the grocery price | Alkalinity |
| Stabilizer (CYA) | Protecting chlorine from sunlight — once a season, not routinely | Cyanuric acid, "conditioner" | CYA / stabilizer |
| Calcium chloride | Raising hardness — only if yours is genuinely low | Ice melt, in a different bag | Calcium hardness |
Salt instead of liquid chlorine if you run a generator, and the bleach strength converter is worth a look before you buy chlorine by price — the cheapest jug is often the dearest per ppm.
What we'd skip
The long lists get long by including things that treat symptoms, duplicate something you already own, or solve a problem good chemistry wouldn't have created. Our honest short list of what to leave on the shelf:
| Commonly sold | Why we'd skip it | Instead |
|---|---|---|
| Algaecide, as routine maintenance | Chlorine at the right level for your CYA already prevents algae. Most algaecides are a copper or quat compound that can stain or foam, bought to compensate for a chlorine level that was too low | Get FC right for your CYA — see the chlorine / CYA relationship |
| Phosphate remover | Phosphates feed algae, but so does sunlight and you're not buying a remover for that. Algae in a properly chlorinated pool doesn't grow regardless of phosphate level | The same fix: chlorine at the right level |
| Chlorine floaters and trichlor feeders | Convenient, and they raise your CYA every single day they run — until your chlorine target has quietly doubled and nothing works any more | Liquid chlorine or a salt cell; see liquid chlorine vs tablets |
| "Shock" sold as a branded product | It's chlorine, usually cal-hypo, at a markup and in a bag that doesn't say how much is in it. Cal-hypo also adds calcium, which some pools can't afford | Dose deliberately with the shock calculator |
| Clarifier, as a standing purchase | Genuinely useful on a sand filter with balanced water. Bought as a reflex it just makes a chlorine or filter problem look better for a day | Diagnose first — cloudy water has four causes |
| Pressure-side cleaners needing a booster pump | The cleaner is cheaper than a robot, then the booster pump runs for hours a day and costs more than the difference | A robot, or an inexpensive suction-side cleaner |
It isn't usually dishonesty — it's that a store's water test hands back a printout of products, and the printout has no way to say "nothing, wait a week." Chemicals are also the high-margin, high-repeat part of the business in a way a $60 cover never will be. The reason this site keeps saying "test first" is that a reading you took yourself is the only version of the advice with nothing riding on the answer.
The safety items that aren't optional
These don't appear in "best pool gear" roundups because nobody earns much on them, which is a poor reason to leave them out. A life ring or rescue hook on a pole, mounted where it can be reached rather than stored in the shed. Barriers, gates and alarms to your local code — requirements vary by state and county, and they're the one area of pool ownership where "close enough" has consequences that don't wash out. Anti-entrapment drain covers to the current standard if your pool is older; the failure mode here is severe and the fix is inexpensive.
And for the chemicals above: store them separately, in a dry ventilated place, in their original containers. Never mix chlorine and acid — the reaction produces chlorine gas. Always add acid to water, not water to acid, and never mix two chemicals in a bucket "to save a trip." Nearly every serious pool-chemical injury comes from combining products that were individually fine.
How gear gets covered here
When product recommendations do go up, they'll follow the same rules as everything else on this site. Specs over vibes — head curves, watts at speed, cell output, filter micron ratings, and the math worked out on the page. The cheap answer named when it's the right one, including "you don't need this." Affiliate links disclosed wherever they appear, and never a reason to recommend the dearer thing; our affiliate disclosure spells out exactly how that works.
Until then, the calculators are the honest version of a buying guide: they tell you the size you need, what it will cost to run, and occasionally that the purchase isn't worth it for your pool. Start with the test dashboard if you're not sure which problem you actually have — most gear questions turn out to be chemistry questions wearing a catalog.