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Can Pool Algae Be White? Types & Treatment Guide

Algae Green Pool Medium 3-7 days 20 views

White stuff growing in my pool - is this some weird algae?

I'm dealing with this white, slimy growth all over my pool walls and I'm honestly confused. I've been treating it like regular green algae - shocked it multiple times, balanced my chemicals, the whole nine yards. But this white stuff just keeps coming back and it doesn't look like any algae I've dealt with before.

Is white algae even a thing? Or am I dealing with something completely different here? The texture is almost... fluffy? And it seems to stick to surfaces more than regular algae. I'm starting to think I need a different approach but I don't want to keep throwing chemicals at the wrong problem.

Dear Matt M.,

Quick Answer

Pool algae is typically green, but white growths in pools are usually white water mold, pink slime bacteria, or biofilms rather than true algae. These require similar shock treatment but may need additional scrubbing and filtration.

Tools & Supplies Needed

pool test kit liquid chlorine pool brush muriatic acid skimmer net

Find on Amazon: Taylor K-2006 Pool Test Kit , Liquid Chlorine Pool Shock , Pool Brush Steel Bristle

Understanding White Pool Algae and Look-Alikes

While traditional pool algae is typically green, yellow, or black, pool owners sometimes encounter white or colorless growths that appear algae-like. Technically speaking, true algae is rarely completely white, but several organisms commonly found in pools can appear white and behave similarly to algae in terms of treatment needs.

What Causes White Growths in Pools

The white, slimy, or filmy substances you're seeing are most likely one of these organisms:

White Water Mold

White water mold (Fusarium or Aspergillus species) appears as white, gray, or colorless stringy growths that feel slimy to the touch. This fungal organism thrives in warm water with low sanitizer levels and often appears in areas with poor circulation like behind ladders, in skimmer baskets, or around return fittings.

Pink Slime (White Variety)

Despite its name, pink slime bacteria can appear white, clear, or colorless. This biofilm-forming bacterium creates a slippery coating on pool surfaces and is particularly common in areas where organic matter accumulates.

Biofilms

Various bacteria can form clear to white biofilms that protect colonies of microorganisms. These appear as thin, slippery films on pool surfaces and equipment.

How to Identify White Pool Organisms

To properly identify what you're dealing with, examine these characteristics:

Testing Your Water Chemistry

Before treating, test your water using a reliable test kit like the Taylor K-2006. You'll need accurate readings for:

White water mold and similar organisms typically appear when free chlorine levels drop below 1.0 ppm or when the FC/CYA ratio is inadequate for proper sanitization.

Treatment Protocol for White Pool Organisms

Step 1: Remove Physical Growth

Start by physically removing as much of the white growth as possible:

  1. Brush all pool surfaces vigorously with a steel brush (concrete) or nylon brush (vinyl/fiberglass)
  2. Clean out skimmer baskets, pump baskets, and any pool equipment
  3. Remove and clean pool accessories like ladders, toys, and cleaning equipment
  4. Vacuum debris to waste if possible, or use a manual vacuum

Step 2: Shock Treatment Using SLAM Method

Apply the SLAM (Shock Level And Maintain) protocol:

  1. Calculate your shock level based on your CYA reading using the FC/CYA chart
  2. For CYA of 30-50 ppm, maintain FC at 12-20 ppm during treatment
  3. Add liquid chlorine (sodium hypochlorite) - typically 1 gallon per 10,000 gallons raises FC by 1 ppm
  4. Run your pump continuously during treatment
  5. Test FC every few hours and add chlorine to maintain shock level

Step 3: pH Management

Maintain pH between 7.2-7.4 during treatment for maximum chlorine effectiveness. Use muriatic acid to lower pH if needed, adding approximately 1 quart per 10,000 gallons to lower pH by 0.2.

Step 4: Enhanced Filtration

Since these organisms can clog filters quickly:

  1. Clean or backwash your filter daily during treatment
  2. Consider using a clarifier to help filter capture small particles
  3. Run your pump 24/7 until the problem is resolved

Prevention Strategies

Preventing white organisms requires consistent maintenance:

When to Seek Professional Help

Contact a pool professional if:

Safety Warning: Always add chemicals according to manufacturer instructions, never mix different chemicals, and ensure proper ventilation when handling pool chemicals.

Timeline and Expectations

Expect the treatment process to take 3-7 days of consistent SLAM protocol. The white organisms should begin breaking apart within 24-48 hours, but maintaining shock levels ensures complete elimination and prevents quick reformation.

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Tags: #white algae #white water mold #pink slime #biofilm #SLAM method
For informational purposes only. Information may not be complete or accurate. Always verify before use. For complex pool issues, consult a qualified pool professional. See our Terms of Service.