I have had a terrible cyanobacteria problem for months. I have tried all the recommended cures, no light, increased flow, decreased flow, decreased feeding, checking parameters, more frequent water changes, less frequent water changes and siphoning out the cyano as is possible.. None of these had any lasting impact. I tried chemiclean out of desperation and have been very pleasantly surprised at its effectiveness and apparent lack of negative effects on the tank. Within 3 days of following the directions, my tank looks amazing and has continued to for 10 days. I will see what the long term effects are. The coral and fish have never looked happier. In following the directions I had to estimate water volume and decided that my 75 gallon tank/ 23 gallon sump had about 50 gallons of water once all the rock, sand and equipment volume was deducted. Maybe those who have problems have over estimated their water volume and thus overdosed the product. I did put a air stone in the sump as they directed, although I do not think this makes any logical sense as most believe that very little oxygen exchange occurs with bubbles, but mostly at the water air interface.
I know some have had tank crashes with its use, but for me it has performed better than expected.
As a side note, I do think the manufacturer (Boyd) and for that matter all manufacturers of treatment products we use should publish the ingredients in their products. It should be a requirement to sales in the U.S. as it is in some European countries that the end user knows what is in the product. Saying that it is proprietary is nonsense argument. Whether it is an erythromycin salt, flocculant or oxidizing agent, let the purchaser make an informed decision whether to use a product or not and not leave it up to faith and chance.