Pool care guides
Plain-English help for the problems every pool owner runs into.
How to Balance Pool Water
Balance six readings in the right order: alkalinity, pH, calcium hardness, cyanuric acid, then chlorine last, with a final saturation check. Why the order matters and the calculator for each dose.
How to Clear a Cloudy Pool
Find whether it is chemistry or filtration, and fix it in the right order.
How to Get Rid of Pool Algae
The SLAM method that actually clears a green pool, step by step.
Ideal Pool Chemistry Levels
The target ranges for every reading, and which calculator fixes each one.
How to Shock a Pool
When to shock, which type to use, and how much, step by step.
Hot Tub Maintenance
The short, repeatable routine that keeps spa water clear.
How to Lower pH in a Pool
Acid, the right amount, and why pH keeps climbing.
How to Raise pH in a Pool
Soda ash or free aeration, and which to use when.
How to Lower Alkalinity in a Pool
The aerate-and-acid method that drops alkalinity without crashing pH.
How to Lower Cyanuric Acid
Why you drain to lower CYA, and how to stop it climbing.
How to Open a Pool
The right order to uncover, clean, balance, and clear in spring.
Pool Maintenance Schedule
What to do daily, weekly, and monthly to avoid green-water weekends.
How to Raise Alkalinity in a Pool
Baking soda, how much, and why it steadies pH.
Do Phosphate Removers Work?
The honest take on pool phosphates and what actually stops algae.
How to Get Rid of Black Algae
Break the protective cap, brush hard, and hold high chlorine.
How to Get Rid of Mustard Algae
Why yellow algae returns, and the cleanup step most people skip.
How to Winterize a Pool
Balance, lower the water, clear the lines, dose, and cover.
How to Lower Chlorine in a Pool
Sun, neutralizer, or dilute, and when it is safe to swim.
How to Raise Chlorine in a Pool
Add liquid chlorine or cal-hypo, circulate, and aim for 1 to 3 ppm. How to raise it fast, why it sometimes will not come up (cyanuric acid or demand), and how to do it in a saltwater pool.
How to Drain a Pool
When to drain, the real risks, and why partial usually beats full.
Why Is My Hot Tub Foaming?
What causes spa foam and how to fix it for good, not just hide it.
Pool Pump Repair: Common Problems and Fixes
Why a pump loses prime, hums, leaks, or quits, and which fixes are worth doing.
Pool Chemicals: What You Actually Need
The short list that matters: sanitizer, pH, alkalinity, stabilizer, shock. What each does, the order to add them, and what to skip.
How to Clean a Pool Filter
Clean cartridge, sand, and DE filters the right way, when to do it, and what cleaner to use.
Pool Stabilizer (Cyanuric Acid): What It Does
What pool stabilizer is, the level to aim for, how to add it, and why baking soda is not the same thing.
How a Pool Skimmer Works
What the skimmer does, the right water level, why it stops sucking, the weir door, and how many a pool needs.
Above-Ground Pool Decks
What a deck costs, the best material, layouts that work, permit rules, and why it must never rest on the pool wall.
How to Install an Above-Ground Pool
What installation costs, whether to DIY, how to level the ground, what to put underneath, and the startup chemistry.
How to Vacuum a Pool
Manual vacuum step by step, when to set the filter to Waste, priming the hose, vacuuming algae and fine dust, and manual versus robotic.
How Long to Run a Pool Pump
How many hours a day to run the pump, calculating run time from turnover, variable-speed versus single-speed, day versus night, cost, and when to run continuously.
How to Remove Pool Stains
Identify organic versus metal stains first, then clear them with chlorine or ascorbic acid, and keep them from coming back.
How to Backwash a Sand Filter
The step-by-step at the multiport valve, when to do it (the pressure rule), how long to run backwash and rinse, why you cannot skip the rinse, and whether to backwash before or after shocking.
How to Change the Sand in a Pool Filter
Drain and open the tank, scoop or vacuum out the old sand, cushion the laterals with water, add the right amount of fresh media, then backwash before you filter. How much sand you need, how often it is due (every 3 to 5 years, not yearly), and what it costs to DIY versus hire out.
Why Won't My Pool Hold Chlorine?
Diagnose whether it is stabilizer, algae, or chloramines eating your chlorine, then fix the right cause in order.
How to Lower Calcium Hardness
No chemical removes calcium; here is how to actually lower high calcium hardness with a partial drain or reverse osmosis, manage it when you cannot drain, and stop it climbing.
How to Raise Calcium Hardness
Low calcium hardness means soft, corrosive water. Raise it the same day with calcium chloride: how much you need, the ideal range for plaster and vinyl, and why baking soda does not do it.
How to Find a Pool Leak
Confirm it with the bucket test, narrow it to plumbing or structure with the pump-on/pump-off test, then pinpoint the hole with dye. The common leak spots and which repairs you can do yourself.
How to Get Rid of Pool Foam
Foam comes from a surfactant in the water: cheap algaecide, body oils and lotions, or low calcium hardness. Find the cause, clear it fast with a defoamer and a partial drain, and stop it coming back.
How to Heat a Pool
The fastest way is a gas heater; the cheapest is a solar cover plus solar panels or a heat pump. How the three heater types compare, how long heating takes, what it costs, and how to heat a pool for free.
Saltwater Pool Maintenance
A saltwater pool is a chlorine pool that makes its own chlorine. The routine, the chemistry targets, how to run the salt cell, and why pH is the number you chase most.
How to Test Pool Water
Test strips, drop kits, and digital testers compared, what to test for, where and when to take the sample, and how to read the results.
How to Convert a Pool to Saltwater
Almost any chlorine pool can be converted by adding a salt chlorine generator. What equipment you need, the step-by-step, what it costs (about $600 to $2,500), and whether it is worth it.
How to Get Rid of Water Bugs in a Pool
The bugs are water boatmen or backswimmers, and they came for the algae. How to tell them apart, clear them out by removing their food source, whether backswimmers bite, and how to keep them from coming back.
How to Remove Calcium Scale From a Pool
The chalky white or gray crust on your tile is calcium scale, not high calcium hardness. How to tell carbonate from silicate with an acid test, remove it from tile with pumice, vinegar, or bead blasting, and balance the saturation index so it stops coming back.
How Long After Shocking a Pool Can You Swim?
Wait until free chlorine falls back to 1 to 3 ppm, usually 8 to 24 hours after a chlorine shock, and test the water rather than watching the clock. Why the wait matters, how non-chlorine shock lets you swim in 15 minutes, and the wait time for every other pool chemical.
How to Start Up a New Pool
Fill, circulate, then balance in order (alkalinity, pH, calcium hardness, cyanuric acid) before chlorine last. The full startup sequence, the chemicals you need, how new plaster differs, and how soon you can swim.
Why Does My Pool Smell Like Chlorine?
The strong chlorine smell is chloramines, not too much chlorine. It means the pool has too little free chlorine for its contaminant load. What chloramines are, why the smell means you shock rather than back off, and how to clear it for good.
Why Is My Pool Green but the Chlorine Is High?
A high chlorine reading is not the same as working chlorine. The four real causes are high cyanuric acid, high pH, reading total instead of free chlorine, or metal rather than algae. How to tell which one you have and clear the water without draining.
How to Get Rid of White Water Mold and Pink Slime
White water mold looks like shredded tissue paper and pink slime is a pink bacterial film, and neither is algae. Both are biofilms that hide from chlorine, so the fix is to physically break them up, clean the filter that harbors them, and hold a high chlorine level until they stop coming back.
How to Prime a Pool Pump
Priming a pool pump means filling the housing with water so it can pull water from the pool. The step-by-step, why a pump won't prime or won't stay primed, how to clear an airlock, and what to do when it runs but moves no water.
How to Get Rid of Dead Algae in a Pool
Chlorine kills algae but cannot make it disappear. Remove the gray, cloudy dead algae by filtering it out, running the pump around the clock, vacuuming the settled layer to waste, or dropping it with a flocculant. How long it takes and how to do it without a vacuum.
How to Get Rid of Sand in the Bottom of a Pool
Sand on the pool floor is almost never real sand. It is usually a broken sand filter leaking its media through the return jets, blown-in dirt, or mustard algae that looks like sand. How to tell them apart with a finger test, vacuum the sand out to waste, and stop it coming back.
How to Remove Metals From Pool Water
Iron, copper, and manganese stain the pool and turn the water green or brown the moment you shock. A sequestrant only hides dissolved metal; actually removing it takes a metal-absorbing pack, a partial drain with a pre-filtered refill, or reverse osmosis. How to confirm which metal you have, remove it, and stop corrosion and fill water from putting it back.
How to Shock a Saltwater Pool
Yes, you still shock a saltwater pool, because the salt cell cannot out-produce algae or a heavy bather load. When to shock, whether to use the boost button or add shock by hand, which shock is best (and which to avoid), and how much.
What Is Chlorine Lock?
Chlorine lock is the pool-store name for chlorine that tests present but will not sanitize, but there is no real lock. It is almost always too much cyanuric acid throttling your chlorine, or a false zero from a test reagent bleached out by very high chlorine. How to tell which, and how to fix each.
Can You Put Chlorine Tablets in the Skimmer?
You can, but you should not. Trichlor tablets in the skimmer dissolve into a concentrated, acidic slug every time the pump shuts off, and that slug corrodes the pump, the heater's copper exchanger, and the plumbing when the pump restarts. Why it damages equipment, where to put tablets instead, and whether a floater or an automatic chlorinator is better.
Is It Safe to Swim in a Green Pool?
No. Green water means the chlorine has lost the fight, so the pool is unsanitized and you cannot see the bottom, which is both a health and a drowning hazard. When a faint tint is lower risk, the real risks, and how to make the water safe to swim in again.
How to Clean Pool Tile and the Waterline
The greasy ring at the waterline is a scum band of body oils, sunscreen, and pollen, not calcium scale, so acid does nothing and a cleaner or melamine sponge takes it off. How to tell scum from scale, clean the tile without draining, match the tool to your surface, and keep the scum line from coming back.
How to Acid Wash a Pool
Acid washing drains a plaster pool and strips a thin top layer to erase deep stains, heavy scale, and ground-in algae. When it is worth it, the step-by-step, what it costs (about $150 to $450 for a pro), how often a plaster surface can take it, and the safer fixes to try first. Plaster and concrete only, never vinyl or fiberglass.
Why Does Pool Water Turn My Hair Green?
It is copper in the water, not chlorine. Chlorine only oxidizes the dissolved copper into the deposits that bind to hair and leave the same green tint as an old copper roof. Where the copper comes from (algaecide, a corroding heater, low pH, fill water), why light and bleached hair shows it most, how to lift the green out with vitamin C or a chelating shampoo, and how to fix the water so it stops.
How to Get Rid of Frogs in a Pool
Frogs come to a pool for the still water to breed in and the insects drawn to the lights. How to net a trapped frog out or give it an escape ramp before it drowns, why chlorine will not kill them and overdosing only harms the pool, how to remove eggs and tadpoles, and how to keep frogs out with darkness, a cover, and clean water.
How to Get Rid of Leaves in a Pool
Getting leaves out of a pool is mechanical, not chemical. Skim the surface with a leaf rake before leaves sink, pull the sunken ones off the bottom with a leaf vacuum or by vacuuming to waste, and stop the next batch with a leaf net and a daily skim. Why chlorine will not dissolve leaves, how rotting leaves stain and feed algae, the best tool for a full pool, and how to clean up after a storm.
Borax in a Pool: What It Does
Borax raises pH with a smaller alkalinity bump than soda ash, and at 30 to 50 ppm it buffers pH and mildly suppresses algae. What borax does, how to add it in stages, borax versus soda ash, the borate method, boric acid versus borax, and whether it is safe to swim in.
How Much Does It Cost to Run a Pool?
What it really costs per year: pump electricity, chemicals, water, heating, and opening and closing. A modest unheated pool runs about $1,200 to $1,800 a year; heating, a single-speed pump, or a service pushes it to $3,000 to $5,000 or more. Where the money goes and how to cut it.
How to Store Pool Chemicals Safely
Store them cool, dry, dark, and sealed in original containers, and keep chlorine, acid, and different chlorine types physically apart. Where to store them, what to never store together, how long each lasts, and how to overwinter leftovers at closing.
Why Is My Pool Cloudy After Rain?
Rain clouds a pool by diluting chlorine, dropping pH and alkalinity, and washing in dirt, pollen, and phosphates all at once. Test first, raise chlorine and fix pH, then run and clean the filter. Why rain does it, what to do first, whether to shock, whether to run the pump in a storm, and how to stop it next time.
When Should I Close My Pool for Winter?
Close when the water stays consistently below 60°F, not on a calendar date, since algae go dormant below 60°F. Why temperature is the trigger, when that happens by region, why closing too early breeds algae, why closing too late in a freeze climate cracks plumbing, and when a warm-climate pool needs no closing at all.
How to Clean a Salt Cell
Inspect the cell first, rinse loose scale off with a hose, and soak it in a 4-to-1 water-to-muriatic-acid solution only if hard calcium scale remains. How much acid to use, how long to soak, how often to clean, why over-cleaning kills the plate coating, and how to keep the cell from scaling up again.
Why Is My Pool Water Brown?
Brown pool water is almost always oxidized iron or manganese from the fill water, tannins leached from rotting leaves and debris, or a heavy load of dirt and dead algae. Chlorine clears the organic kinds and makes metal worse, so diagnose first with a chlorine cup test. How to tell metal from tannins and clear each without draining.
Why Are There Air Bubbles Coming Out of My Pool Jets?
A steady stream of air bubbles from the return jets means air is being pulled into the suction side of the plumbing, between the skimmer and the pump impeller, then blown back into the pool. Usually a low water level or a dried-out pump lid o-ring. How to confirm a suction-side air leak, find where the air enters, and fix it before it damages the pump.
Salt Chlorinator Troubleshooting
A salt chlorinator that stopped making chlorine is almost always low salt, a scaled cell, cold water, or low stabilizer, not a dead unit. Diagnose the real cause in order, the signs a cell is actually worn out, how to reset the system, and how to keep chlorine up while you fix it.
How to Lower a Pool's Water Level
Lower the water a few inches with a submersible or cover pump, or the filter's Waste setting on a sand or DE filter, and stop at the middle of the skimmer. How far to lower it, the fastest way, what to do after rain overfills the pool, and why a small drop is safe when a full drain is not.
Which Way Should Pool Return Jets Point?
Point return jets slightly down and all the same way so the whole pool turns in one slow circle and the surface rides toward the skimmer. Why circulation matters more than runtime, up versus down, aiming multiple jets, jet depth and plumbing, and clearing the dead spots where algae starts.
How to Keep Bees and Wasps Away From a Pool
Bees and wasps come to a pool for water, not to sting you. Why they pick your pool and keep coming back, how to draw them off with a better water source, how to handle a swarm or a wasp nest, the smells that deter them, and why chlorine does nothing.
How to Get Rid of Mosquito Larvae in a Pool
Mosquito larvae (wigglers) only appear when a pool goes still and loses its chlorine. Run the pump, restore chlorine, and skim them off the surface. Why a working pool never breeds them, what kills them, whether it is safe to swim, and how to keep the cover from becoming the nursery.
How to Keep Ducks Out of a Pool
Ducks land on a pool because it looks like a calm, safe pond from the air. Break up the still surface, cover the water, cut off food and shelter, and add a motion deterrent. Why they keep coming back, why their droppings carry germs chlorine does not kill on contact, and how to sanitize the pool after they have been in it.
Why Is My Pool Heater Not Working?
A pool heater that will not fire or heat is almost always a water-flow problem, not a dead heater. Check flow and the filter first, then gas supply and ignition on a gas heater or cold air and a dirty coil on a heat pump, then the safety switches. How to diagnose each cause in order, reset the unit and clear an error code, and decide whether to repair or replace.
Why Is My Pool Filter Pressure High?
High filter pressure almost always means a dirty, clogged filter forcing the pump to strain. What counts as normal (your own clean baseline, usually 10 to 25 psi), the 8-to-10-psi rule for when to clean, why pressure spikes fast after shocking or a pollen bloom, how to lower it by filter type, what else besides dirt raises it, and why you must never open a filter under pressure.
How to Cool Down a Pool
The cheapest way to cool a pool is to run the pump and fountains overnight so evaporation sheds the day's heat; the on-demand fix is a pool cooler or a reverse-cycle heat pump. Why evaporation does the work and why humidity decides how well it works, running solar panels at night, removing the solar cover, why ice does almost nothing, and what temperature a pool should be.
Why Is My Pool Still Cloudy After Shocking?
Shock kills what is in the water but does not clear it, so a pool that turns cloudy or milky right after a shock is normal and usually means the shock worked: the dead material is now a filtration-and-time job, not a reason to add more shock. How long clearing takes, why a pool stays green rather than just cloudy, and when more shock actually helps versus when it just wastes chemicals.
How to Blow Out Pool Lines for Winter
Lower the water, drain the equipment, then push low-pressure, high-volume air through each line until it bubbles out the pool side and plug it under air. What tool to use (a shop vac beats an air compressor), how much pressure is safe, the main-drain air lock, the skimmer freeze plug, and when antifreeze is enough.