Foam and Algae in Concrete Pond: Protein Skimmer Solution?

Persistent Foam and Suspended Algae in Mature Concrete Pond

A 5,000-gallon, 2-year-old concrete pond (acid-treated, rubber-painted) with excellent test results still suffers from chronic foam (especially at night) and suspended algae despite a UV sterilizer, biofilter, and external pump.

Foam Causes & Solutions

• Organic buildup: Food waste, fish waste, decaying plants
• Spawning activity: Fish/frog spawning increases organics
• Remedies: Water changes, fresh activated carbon in filter, protein skimmer (foam fractionator), anti-foam chemicals

Algae Despite UV

• Check UV lamp age and sleeve cleanliness
• Verify proper flow rate through UV unit
• Add shade, plants, barley straw, beneficial bacteria
• Protect plants from koi if present

Protein Skimmer Inquiry

Owner interested in protein skimmer for 5,000-gallon pond. Marine models may adapt; pond-specific units exist but can be hard to source.