Foam in water fountains can be a problem if you have undissolved organics in your water.  Typically, foam is simple to get rid of with Foam-Nix Defoamer.  This fountain care product is great for table top and other indoor fountains and outdoor patio ponds or fountains.  It will eliminate foam in your fountains fast and it is safe for fish, plants and wildlife.  You may also see an occurrence of foam if your fountain is located in direct sunlight as undissolved organics may be higher than normal due to faster evaporation rates. 

Small Fountain Protector: What it is and how it works.

Natural enzymes safely break down organic contaminate. A food-grade enzyme, non-toxic, biodegradable, bacteria free and 100% environmentally friendly. Safe for all surfaces.

Safe for wildlife, aquatic life and pets, when used as directed. Small Fountain Protector prevents; sludge, ammonia, cloudy water and mineral deposits from forming and keeps fountain pumps and water lines free from organic buildup for maximum efficiency. It enhances the performance of all indigenous bacteria (good bacteria) naturally found in fountains.

Use weekly or as often as you replace water for maximum performance. One (1) capful treats 5 gallons of fountain water. Dirty fountains can also benefit from Small Fountain Protector and will begin to safely breakdown organic contaminants and loosen mineral deposits. For badly contaminated fountains, use product as directed. It will take several weeks to establish clean and clear water. For best results, start with Small Fountain Protector upon opening of fountain. Fountain Protector is not a chemical, but natural enzymes, which need time to work properly.