Green Pool: DIY Steps and When to Call a Pro in Texas

How do I clear a green pool myself?

Work in order: test, remove debris, clean the filter, brush, raise chlorine, and run the pump. Skipping steps is why many green pools take twice as long. Always follow the label on each chemical. This post gives the order of steps. It does not give doses, because the right dose depends on your product, your pool volume, and your readings.

Green water means green algae has taken over. It is the most common type and the easiest to kill, according to Pool Founder. If your pool is green because of a storm, start with why pools turn green after a storm.

What are the steps?

1. Test the water. Check free chlorine, pH, and cyanuric acid. CDC says a DPD test kit is the most accurate home option, and test strips are less accurate. Hydra says high stabilizer, above 80 ppm, makes shock far less effective and may need a partial drain.
2. Adjust pH. Both Hydra and Pool Founder say chlorine works better at lower pH, around 7.2 to 7.4. Hydra says to lower high pH before shocking. Use only products and amounts your label allows.
3. Clear the big debris. Use a leaf net. Empty the skimmer and pump baskets. Do not vacuum yet, since it clogs the filter right away.
4. Clean the filter. Start with a clean filter. Cartridges can be hosed off, sand filters backwashed, and DE filters recharged. Plan to clean it again during recovery.
5. Brush every surface. Walls, floor, steps, benches, behind ladders, around drains. Hydra suggests a steel brush for plaster or concrete and a nylon brush for fiberglass or vinyl.
6. Raise chlorine with shock. Use a shock product exactly as the label says. Hydra suggests doing it in the evening because sunlight burns off chlorine. Pre-dissolve granular shock as the label directs. Do not add it through the skimmer.
7. Run the pump nonstop. Both sources say to keep it on until the water clears.
8. Retest and repeat. Test chlorine every 12 hours or so. Clean the filter when pressure rises. Brush daily.
9. Vacuum dead algae last. Once the water is cloudy white with no green tint, the algae is dead. If you can vacuum to waste, that sends it out of the pool. Check local water rules first.
10. Rebalance. Test all chemistry and clean the filter one last time.

Hydra describes the color path as green, then cloudy green, then cloudy white, then hazy, then clear. Each stage means progress.

How bad is it?

Hydra grades a green pool by what you can see. Its timing is a rough estimate from one company.

When should I call a pro?

Call when the work is bigger than your time, filter, or comfort with chemicals. Signs include:

• You cannot see the bottom, or you see a murky green or black-green.
• The filter keeps clogging and you cannot keep up.
• The water does not improve after a couple of days of correct treatment.
• You see spots that may be black algae or mustard algae. Our post on algae types helps you tell them apart.
• Stabilizer is very high and you are unsure how to lower it.
• The pump, filter, or other equipment seems to be failing.

Marina Pool Services offers algae treatment. Its algae page says the team can get rid of algae fast and also clean the filter, since algae often builds up there too. A pro can also look at the equipment that may have caused the problem.

What mistakes slow a cleanup?

Hydra says most homeowners add chemicals at random and waste money. These are the usual slips:

• Shocking before checking pH or stabilizer, so the chlorine cannot do its job.
• Vacuuming first, which clogs the filter at once.
• Skipping the brush, so algae on the surfaces never meets the chlorine.
• Shocking in strong afternoon sun, which burns off chlorine before it works.
• Shutting off the pump overnight while the water still has green in it.
• Quitting early. Cloudy white water means the algae is dead but the particles are still in the water.

How do I stop it from returning?

Fix the root cause. Hydra’s list of common causes includes low chlorine, too little filter time, a storm, high stabilizer, and a week away. Its prevention list includes keeping chlorine in range, running the pump enough in warm months, cleaning the filter on schedule, and watching stabilizer. CDC adds that chlorine and pH are the first defense, and it recommends routine testing.

Is it safe to handle these chemicals?

Pool chemicals can injure people when mixed or handled without protection, says CDC. Store each product by itself, in its original labeled container, dry and away from heat. Never mix chemicals. Do not guess at doses.

For more, see the green pool cleanup guide.

Next step

If you would rather hand it off, read about Marina’s algae treatment. Call (817) 896-1120 or use the quote form to ask for a free estimate, available for qualifying services.