[Surfhead]

I'm not an expert, I am just reststing what I have read posted by others smarter then I.

quote from JR

"I would suggest that surface appearance would be different depending on ‘species’ of DOC that was dominate? DOCs can be protein based, carbohydrate based or lipid based. Fish food byproducts ( either passed through the fish or broken down by bacteria), fish slime, algae contents all make up a mix or chains of molecules. But when visible to the naked eye, we are usually looking at POCs on the water surface. Since DOCs are by definition ‘dissolved’ they are not usually visible until this foaming action is encouraged. I have seen ponds with really poor circulation and over crowded conditions that actually form slicks of lipids combined with particulate matter floating on the surface. And many of us are familiar with the yellow stain in water rich in protein and natural dyes produced by algal and bacterial action. If the water foams you have the combination but if it is yellow and doesn’t foam you are looking at organic dyes.
This brings us back to the idea that pond water- water in a closed system- is in a constant state of deterioration. Desirable things are being lost and undesirable things are being built up. The only reliable intervention for long term insurance is a water change. In between, sump flushing, moderate feeding matched to the limitations of a given pond, foam fractionation, carbon or resin use, clay etc. will help keep the water ‘sweet’.
The mystery of bakki shower marketing is – where does this DOC and POC go? If the answer is it is in circulation and removed by constant water change then fine! We should be able to measure that. Bacteria count will reveal some of the answer. Foam fractionation study should provide more evidence. I’m using a POWERED Euro foam fractionator at some point to measure foam content. An expensive unit at $2000 but a super performer."