I used 2ml H2O2 per US gallon on a 30g aquarium to eradicate thread algae. I dosed two days running, 60ml, midday without removing fish or turning off the filter. There were no casualties, except the thread algae which was completely gone at the beginning of the third day. Tonina sp., Anubias, Marsilea sp. all survived. The fish showed no stress.
I used H2O2 to spot treat BBA on another aquarium without much success. Spot treating is an art, perhaps, which requires a good sized long syringe. In the end removal of rocks which had BBA (without returning these rocks), cleaning of the filter tubing with H2O2, and washing the filter and media in dechlorinated water, and vacuuming the substrate carefully was the key to eradicating BBA - along with increasing the CO2 level and ensuring it was consistent (in this case changing from DIY CO2 source to pressurized supply).
Andrew Cribb
I used H2O2 to spot treat BBA on another aquarium without much success. Spot treating is an art, perhaps, which requires a good sized long syringe. In the end removal of rocks which had BBA (without returning these rocks), cleaning of the filter tubing with H2O2, and washing the filter and media in dechlorinated water, and vacuuming the substrate carefully was the key to eradicating BBA - along with increasing the CO2 level and ensuring it was consistent (in this case changing from DIY CO2 source to pressurized supply).
Andrew Cribb
