Topic

Pool Water Care

Clear water is a routine, not a product. These guides cover the routine.

40 guides on this topic

Something wrong right now? Work through it in two or three questions

Hands in green rubber gloves rinsing a white pleated hot tub filter cartridge with a hose nozzle, the cartridge standing on wet stone pavers beside a hot tub cabinet

Spas & Hot TubsHow-to

How to Clean a Hot Tub Filter, and When to Replace It

How Hot Spring, Jacuzzi, Sundance, Caldera and Bullfrog say to clean a hot tub filter, how often, what to soak it in, and when to replace it.

10 minUpdated Oct 1, 2026

A blue bubble solar cover rolled onto a white reel at the edge of a sunlit pool, pale stone paving in front and a rendered wall with agaves and grasses behind

Water ChemistryHow-to

How to Lower Chlorine in a Pool

Chlorine reading high? Make sure the test isn't lying, stop whatever is feeding it, and let the sun do the work. When a neutralizer is worth using.

10 minUpdated Sep 27, 2026

A still pool in a walled garden at dusk, an empty wooden lounger with a folded towel in the foreground and climbing greenery on the wall behind

MaintenanceGuide

Pool Care While You're Away

What actually goes wrong while you're gone, how to set the chlorine and the pump before you leave, and when a pool genuinely needs someone to visit.

5 minUpdated Sep 17, 2026

A white pail of coarse white granules with a clear scoop on concrete coping beside a blue pool, granules spilled on the stone and a lawn behind

Water ChemistryHow-to

How to Raise pH in a Pool

Aeration, soda ash or baking soda: which one your test calls for, how much to add, and why pH below 7.0 takes far more than the rule of thumb says.

6 minUpdated Sep 15, 2026

An open white pail of fine white granules with a scoop in it on wet stone coping, a small spill beside it, a long tiled lap pool and lawn behind

Water ChemistryExplainer

Borates in Pool Water: What They Do and What They Don't

Borates slow pH creep and the labels claim algae suppression. What the EPA labels really say, how much to add, the pH catch, and why only draining removes them.

9 minUpdated Sep 13, 2026

A tipped paper sack spilling fine white powder onto wet stone coping with a plastic scoop resting in it, pool water beyond

Water ChemistryExplainer

Baking Soda in a Pool: What It Does

It raises alkalinity, not pH — which is why people add it, get the wrong result, and add more. How much to use, and when soda ash is the right product.

5 minUpdated Sep 8, 2026

A hot tub set into timber decking with its cover folded back and steam lifting off still water, a pool and coastal grasses beyond

Spas & Hot TubsExplainer

Hot Tub Rash: Why It Happens

It is a water problem before it is a skin problem. What lets the bacteria survive a hot tub, and the sanitizer habits that stop it recurring.

5 minUpdated Sep 8, 2026

A capped test vial of pale pink pool water standing on wet dark stone coping, a rectangular pool and fenced pasture behind it

Water ChemistryExplainer

How Long After Shocking a Pool Can You Swim?

The honest answer is not a number of hours. It is a chlorine reading — and knowing which one saves you a day of waiting or an evening of stinging eyes.

6 minUpdated Sep 8, 2026

A graduated measuring jug of clear liquid and a white chemical jug standing on pool coping, desert planting and a stucco wall behind

Water ChemistryHow-to

How to Lower pH in a Pool

Muriatic acid or dry acid, how much to add, and why the pH you keep chasing back down is usually an alkalinity problem wearing a disguise.

5 minUpdated Sep 13, 2026

A hard white calcium crust banded along pool waterline tile, the deposit rough and uneven where it meets clear water

Water ChemistryExplainer

Calcium Hardness: The Number That Only Goes Up

Too low and the water eats your plaster. Too high and it scales everything. Targets by surface, how to raise it, and why lowering it means draining.

5 minUpdated Sep 6, 2026

Three plain unbranded chlorine containers in one row on wet coping at the same scale: a stack of white tablets

Water ChemistryComparison

Chlorine Tablets vs Liquid vs Granular: Which to Use

Every chlorine product adds something besides chlorine — stabilizer, calcium or salt. Pick the one whose leftovers your water can still absorb.

5 minUpdated Sep 6, 2026

Foam sitting on the surface of cloudy hot tub water

Spas & Hot TubsTroubleshooting

Cloudy Hot Tub Water and Foam: What Actually Causes Both

Why hot tubs foam and why they go cloudy, from the spa makers' own manuals, and how to find which cause you have before you buy another bottle of something.

6 minUpdated Oct 1, 2026

A submersible pump sitting on the floor of a partly drained pool with its discharge hose running up over the coping

MaintenanceHow-to

Draining a Pool: When You Have To, and How It Goes Wrong

An empty pool can float out of the ground. When a partial drain is enough, when a full drain is genuinely needed, and the checks that come first.

5 minUpdated Sep 6, 2026

A garden hose feeding a pool through a clear inline cartridge housing clamped to the coping, water running

Water ChemistryGuide

Filling a Pool With Well Water: Metals and Stains

Iron, copper and manganese ride in on the fill water and stain the pool the moment you chlorinate. How to test first, and what a sequestrant cannot do.

5 minUpdated Sep 6, 2026

A hot tub filter cartridge lifted out beside an open hot tub cabinet

Spas & Hot TubsChecklist

Hot Tub Maintenance Schedule: Weekly and Monthly

What a hot tub needs after each soak, each week and each month, by the spa makers' own manuals, and the dissolved-solids test that says when to drain.

6 minUpdated Oct 1, 2026

Bromine granules and a used test strip resting on the flat acrylic edge of a cabinet hot tub

Spas & Hot TubsGuide

Hot Tub Water Chemistry: Targets and Sanitizers

Bromine versus chlorine in a spa, the target ranges that differ from a pool, and why 400 gallons at 102 degrees is a completely different problem.

8 minUpdated Oct 1, 2026

A garden hose refilling an empty hot tub shell

Spas & Hot TubsHow-to

How to Drain and Refill a Hot Tub (Without an Airlock)

The full drain and refill: power off at the breaker first, what each spa maker says to clean the shell with, and how to refill without an airlock.

6 minUpdated Oct 1, 2026

A milky white liquid being poured from a plain bottle into an open pool skimmer, a pale plume dispersing into the water below the surface

Water ChemistryExplainer

Phosphates in Pool Water: When They Actually Matter

Phosphates feed algae, but a high reading is not why your pool went green. What the number means and when removing it is money well spent.

5 minUpdated Sep 6, 2026

One simple rectangular pool, full to the brim with opaque muddy brown water, silt banked across the shallow step at one end

MaintenanceHow-to

Pool After a Flood: Contamination, Silt and Draining

Floodwater is a health problem, not a chemistry problem. What to do first, what to replace, and why the pool stays full while the ground is saturated.

6 minUpdated Sep 6, 2026

Rain dimpling the surface of a pool filled above its skimmer mouth, leaves and small twigs floating, the coping dark and wet

MaintenanceHow-to

Pool After Heavy Rain: What to Do in the First 24 Hours

Rain dilutes your chemistry and dumps organic load in at the same time. The order to work through, and the one thing to do before the storm arrives.

5 minUpdated Sep 6, 2026

A short row of plain white pool chemical buckets and jugs on a garage shelf, lids seated, every label turned away

GuidesGuide

Pool Chemicals Worth Keeping on Hand

Eight products cover a season. Two of them are sold at four times the price under a pool label, and most of the rest of the shelf treats symptoms.

5 minUpdated Sep 13, 2026

A greasy brown scum band on pale waterline tile, sharply defined where the water sits, a sponge just touching one end of it

MaintenanceHow-to

Pool Waterline Scum: Why It Comes Back and How to Stop It

That greasy band at the waterline is body oil, sunscreen and dust. Here's how to remove it properly and stop it returning every week.

5 minUpdated Sep 6, 2026

A gloved hand pouring liquid chlorine from a plain jug into a pool at dusk, the stream catching the last light against dark water

RepairsTroubleshooting

Pool Won't Hold Chlorine? Work Out Which Demand You Have

Chlorine gone by morning means something is consuming it. The overnight test that tells you what, and why ammonia is the one that needs a shocking dose.

5 minUpdated Sep 6, 2026

A small blue cylindrical mineral cartridge held in a gloved hand above an open pool skimmer, the empty basket visible in the throat below

ReviewsReview

PoolRx Review: What the Mineral Cartridge Actually Does

A chelated copper cartridge that genuinely suppresses algae for months. Here's what it does, what it doesn't, and the chlorine advice to ignore.

7 minUpdated Sep 13, 2026

An open plain white tub of chlorine granules with a scoop standing in it on wet coping, the granules coarse and bright

ReviewsBuying guide

The Best Pool Chlorine and Shock in 2026

What to actually keep in the shed. Which chlorine to buy for daily dosing, which for shocking, and the two you should never store side by side.

5 minUpdated Sep 6, 2026

Plain white tubs and a strip bottle grouped on the edge of a hot tub cabinet, the cover folded back, steam lifting off the water behind them

Spas & Hot TubsBuying guide

The Hot Tub Chemicals You Actually Need in 2026

What to buy for a hot tub, starting from your maker's own sanitizer list: chlorine granules, a weekly oxidizer, and bromine only if your tub allows it.

5 minUpdated Oct 1, 2026

An open skimmer lid showing the basket and weir door at the pool edge

EquipmentGuide

Pool Skimmers: How They Work and the Right Water Level

Every part of a pool skimmer explained, why water level decides whether it works at all, and what the equalizer line at the bottom is really for.

6 minUpdated Sep 5, 2026

A clean pool in a warm mild-winter climate, palms and low sun

Seasonal CareGuide

Year-Round Pool Care in Mild Climates: Month by Month

In mild climates, not closing is usually less work and less money. Here's the reduced winter schedule and the freeze protection that makes it safe.

5 minUpdated Aug 8, 2026

Someone vacuuming an above-ground pool from the top rail

MaintenanceGuide

Above Ground Pool Maintenance: What's Different

Smaller volume means faster chemistry swings. Here's what changes, plus the wall and liner care nobody mentions.

6 minUpdated Oct 2, 2026

Rust-brown and blue-green stains on pale plaster under clear water

Water ChemistryTroubleshooting

Pool Stains: How to Identify and Remove Every Type

Metal stains, organic stains and scale all look similar and need completely different treatments. Here's how to tell them apart.

5 minUpdated Jul 9, 2026

Water ChemistryExplainer

Langelier Saturation Index: What LSI Means and How to Fix It

Why two pools with identical test results behave completely differently, and how the saturation index ties all your numbers together.

5 minUpdated Aug 12, 2026

A gloved hand holding a clear test vial of pool water tinted deep pink

GuidesHow-to

How to Test Pool Water (And Why Strips Mislead You)

Sampling technique, which test kit to buy, what to test how often, and the reading errors that send people chasing problems they don't have.

5 minUpdated Sep 13, 2026

Two test vials side by side showing different shades of pink against blue water

Water ChemistryExplainer

Free vs Total Chlorine: What the Numbers Actually Mean

That strong chlorine smell means you don't have enough chlorine, not too much. Here's what free, combined and total chlorine each tell you.

5 minUpdated Sep 13, 2026

Hazy, milky pool water seen from the deck edge, bottom of the pool barely visible

Water ChemistryTroubleshooting

Cloudy Pool Water: Causes and How to Clear It Fast

Six things turn pool water cloudy and only one of them needs clarifier. Work through them in this order and you'll fix it in a day instead of two weeks.

5 minUpdated Sep 12, 2026

A salt cell being inspected out of its union beside a saltwater pool

MaintenanceGuide

Saltwater Pool Maintenance: What's Different and What Isn't

Salt pools need the same weekly care plus three specific things. Here's what changes, what doesn't, and the mistakes that kill cells early.

5 minUpdated Jun 25, 2026

A bottle of muriatic acid and a bag of alkalinity increaser on wet coping

Water ChemistryExplainer

Total Alkalinity vs pH: Why Your pH Won't Stay Put

If you're adding acid every three days, you don't have a pH problem. Here's what alkalinity actually does and how to stop chasing the number.

5 minUpdated May 19, 2026

A skimmer net, brush, test kit and chemical buckets laid out on pool coping

GuidesGuide

New Pool Owner Guide: Your First 30 Days

A pool came with the house and nobody explained it. Here's what to identify, what to test, what to buy and what to ignore in your first month.

6 minUpdated Sep 24, 2026

A homeowner skimming leaves from a clean, well-kept backyard pool

GuidesGuide

Pool Maintenance for Beginners: The Whole Job in One Page

Everything a new pool owner needs to know about keeping water clear, in the order you'll actually need it.

5 minUpdated Aug 30, 2026

Brush, net, test kit and tablets arranged neatly on pool coping

MaintenanceChecklist

The Weekly Pool Care Checklist (Printable)

The exact weekly pool routine, in order, with the twice-weekly jobs separated from the once-weekly ones. Takes about 25 minutes.

5 minUpdated Sep 14, 2026

A drop-test kit open on the coping with vials, reagent bottles and clear blue water behind

Water ChemistryGuide

How to Balance Pool Chemistry: Order, Targets and Timing

The five numbers that matter, the order to fix them in, and the doses that actually work. Written by people who've done this on real pools for 20 years.

9 minUpdated Sep 12, 2026

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Spas & Hot Tubs Water Chemistry Maintenance Guides Repairs Reviews Equipment Seasonal Care