Green Pool? The $200-350 Fix That Homeowners Think Costs Thousands

The cheapest fix we do is the one that scares homeowners the most. You walk into your backyard, the pool is solid green, you cannot see the bottom, and your first thought is "this is going to cost thousands." It costs $200-350. We do green-to-clean recoveries every week across Frisco, and the price shocks people every time — not because it is expensive, but because they expected it to be.

Here is exactly what a green-to-clean costs, what we do during the process, and why the pool that looks like a total disaster is actually one of the simplest problems we solve.

Why Green Looks Worse Than It Is

A green pool is an algae bloom. That is it. The water has no chlorine, algae colonized every surface, and the water turned opaque green. It looks catastrophic. It looks like the pool is ruined. Homeowners google "pool renovation" and "replaster" and start budgeting $10,000.

But algae is not structural damage. It is not a cracked shell. It is not a failed plaster job. It is a chemistry problem with a chemistry solution. The plaster underneath is almost always fine. The equipment underneath is almost always fine. The pool just needs chlorine — a lot of it, all at once, with some elbow grease.

The most expensive-looking pool problem is actually the cheapest to fix. A pump replacement costs $1,200-1,600. A heater repair costs $300-800. A resurfacing costs $5,000-14,000. A green-to-clean costs $200-350. The green pool wins the "looks terrifying, costs nothing" award every time.

What We Actually Do — Step by Step

Day 1: Shock and Brush (30-45 minutes on site)

Test the water first. We need to know what we are working with — especially CYA level. If CYA is above 80 ppm (common in pools that used chlorine tabs for years), we may need to partially drain before the shock will be effective. If CYA is in range, we proceed directly.

Lower pH to 7.2. Chlorine works 3x more effectively at pH 7.2 than at 7.8. Most green pools have drifted to 7.8-8.2 from neglect. We add muriatic acid to bring pH down before shocking — this makes the chlorine we add dramatically more effective and reduces the total chlorine needed.

Triple shock. For a standard 15,000-gallon Frisco pool, we add 3 gallons of liquid chlorine (12.5% sodium hypochlorite). This is triple the normal shock dose. The goal is to overwhelm the algae with more chlorine than it can consume.

Brush every surface. This is the part most DIY recoveries skip, which is why they fail. Algae clings to plaster in colonies with a protective biofilm. Chlorine alone cannot penetrate the biofilm on walls and floors — brushing breaks it up and exposes the algae cells to the chlorine. We brush the entire pool — walls, floor, steps, behind the ladder, around the main drain, inside the skimmer throat. Twenty minutes of aggressive brushing.

Set the pump to run 24/7. The pump stays on continuously until the water is clear. No timer, no schedule, no turning it off at night. Continuous circulation distributes the chlorine and continuous filtration captures dead algae cells.

Day 2-3: Filter Management (15-20 minutes per visit)

This is where the real work happens. The shock killed the algae on day 1 — now the dead algae cells need to come out of the water. They pass through the filter, and the filter loads up fast.

We clean the filter every 24 hours during recovery. For cartridge filters, we pull the cartridge, hose it down thoroughly, and reinstall. For sand filters, we backwash for 3-5 minutes. For DE filters, we bump or backwash and recharge with fresh DE.

We re-test and re-shock if needed. If chlorine dropped below 5 ppm overnight (the algae demand consumed it), we add another 1-2 gallons of liquid chlorine. We keep pushing chlorine until the demand is exhausted — meaning chlorine holds above 5 ppm for a full 24 hours without additional doses.

The water transitions from green to cloudy blue-white. This is progress. The green is gone (algae is dead), but the water is cloudy because dead algae cells are suspended in the water waiting to be filtered out.

Day 3-5: Clear Up

The filter does the heavy lifting now. With the algae dead and the chlorine holding, the filter gradually captures the suspended dead cells. The water goes from cloudy to hazy to clear over 2-3 days.

We vacuum dead algae off the floor. A layer of dead algae settles on the pool floor — gray-green sludge. We vacuum it to waste (bypassing the filter) to remove it quickly rather than forcing it all through the filter.

Final chemistry rebalance. Once the water is clear, we bring all parameters into range — FC 3-4 ppm, pH 7.2-7.4, TA 70-90 ppm, CYA 30-50 ppm. The pool is swim-ready.

What It Costs

Item	Cost
Liquid chlorine (3-5 gallons over recovery)	$30-50
Muriatic acid (pH adjustment)	$10-15
Other chemicals (stabilizer, clarifier if needed)	$10-20
Labor (3-5 visits over recovery period)	$150-250
Total	$200-350

That is it. The pool that looked like it needed $10,000 in work needed $200-350 and a week of attention.

Why DIY Green-to-Clean Often Fails

We take over green pools from homeowners who tried to fix it themselves all the time. The most common mistakes:

Not enough chlorine. They add one gallon instead of three. The algae consumes it overnight and the pool is still green in the morning. They add another gallon. Still green. They give up after a week of incremental dosing that never catches up to the algae demand.

Skipping the brushing. They dump chlorine and walk away. The algae on the walls and floor is protected by biofilm and survives. The water might lighten slightly but never clears because the source colonies on the surfaces keep producing new algae.

Not cleaning the filter. The filter loads with dead algae after day 1 and stops filtering. Flow drops. Circulation stops. The remaining chlorine cannot distribute. The pool stalls in the cloudy phase and never clears.

High CYA blocking the chlorine. They shock with liquid chlorine but their CYA is 120 ppm from years of tabs. The chlorine is locked by the CYA and cannot kill the algae no matter how much they add. They needed to drain first — but they did not test CYA before starting.

When Green-to-Clean Will NOT Work

Black algae. If the growth on the pool surfaces is dark black with raised heads rather than green slime, it is black algae. Black algae has roots that penetrate plaster and a protective cap that resists normal chlorine. Green-to-clean protocol does not kill black algae — it requires a completely different treatment with granular chlorine applied directly to each colony with a wire brush.

Structural issues underneath. If the pool is green AND the pump is dead, the filter is destroyed, and the plaster is delaminating — the green is the least of your problems. We assess the full picture before starting any recovery to make sure the investment in chemicals and labor is not wasted on a pool that needs equipment or structural work first.

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Pool turned green? Hydra Pool Services does green-to-clean recoveries across Frisco for $200-350 — not the thousands you are imagining. Get your pool recovered →