Keep your pool clear & swimmable
Algae Later tells you exactly what to add and when to test — no more guessing, no more green water. Log a reading, get the precise dose, done.
Free · set up your pool in under a minute.
A balanced pool is a cheaper pool
Guessing is expensive. Getting it right the first time isn't.
Stop wasting chemicals
Add the exact amount your pool needs — not a splash-and-hope guess that burns through product.
Never rescue a green pool
A neglected pool can cost €100–300 in shock chemicals and a week out of the water. Catch the drift early.
Skip the pool service
Do it yourself in seconds and keep the €80–150 a visit — the app tells you exactly what to do.
How it works
A simple loop that keeps the water right.
Measure
Dip a test strip and log your pH and chlorine — takes seconds.
Adjust
Get the exact dose to add, scaled to your pool and your products.
Swim
When it's balanced, dive in — and we nudge you when it's time to re-test.
Free pool calculators
No account needed — try them right now.
Pool Volume Calculator
Work out how many litres (or gallons) your pool holds.
Chlorine Dosage Calculator
How much chlorine to add to reach the right level.
pH Up & Down Calculator
How much pH Up or pH Down your pool needs.
Pool Shock Calculator
How much shock to add to reach shock level and clear the water.
Pool acting up?
Green, cloudy or just off — find the cause and the fix.
Common pool problems
Green, cloudy, low chlorine, drifting pH — what's wrong and how to fix it.
Why your pool turned green
Green water is algae from low chlorine — the step-by-step fix and how long it takes.
How much chlorine to add
Hit a safe 1–3 ppm — the rule of thumb, worked examples, and why it won't hold.
How to lower your pool's pH
Pool pH too high? Why it matters and how to bring it back to 7.2–7.6.
How to raise your pool's pH
Pool pH too low? Acidic water stings and corrodes — how to bring it back up.
Cloudy pool water
Clear but not green? The three usual causes and how to get back to clear.
Chlorine won't hold
Chlorine crashing to zero is a demand to shock out — how to diagnose and fix it.
How much shock to add
Reach shock level (10–15 ppm) to clear the water — what it means and how much.