Tom Barr on Excel
and if unable to open for some reason:
To address BBA, it's pretty simple.
1. Reduce light intensity
2. This reduces CO2 demand
3. You can adjust the CO2 back up, you miight try test kits, they sort of work for some, not at all for others, I think watching the fish and plants is the best method given the trade offs, Riccia makes a good bioindicator, when it pearls well the last 1/2 of the day, then you have decent CO2.
4. Add Excel or whatever, and follow the regular dosing labels. 5mls per 10 Gal daily is fine for that. You do not want to double dose and all that, frigging be patient and do not rush to kill fish, fry plants and rush things, be patient, it'll not grow or get worse if you are adding the Excel and correcting the CO2, if so, then you really messed up the CO2 pretty bad.
5. CO2 is not a toy or something to take lightly and be all casual about.
Many folks are then learn the hard lesson and kill their fish or have them gasping at the surface when they added more and then ran off to work all day........then come home all freaked out.
6. So do this CO2 adjustment slowly and carefully, watch the fish and plants.
CO2 is about 99% of all fish deaths in planted tanks, yes..........99%, the others are due to poor filter cleaning, Excel overdosing, H2O2 over dosing etc
All things due to not realizing they are playing with fire and being impatient.
These stat's do not lie, the KNO3/KH2PO4/Trace/GH related deaths? Never met one, but plenty poo poo me over that issue without any associated evidence of any sort of risk.......
Why not tell folks not to add CO2?
7. Lower doses over longer time frames do less damage to the plants/fish, less risk, the algae will die off just fine, give it time.
8. Spend some serious time thinking about CO2 and how to add it, circulate it, measure it, and how to change the demand for it(increase/decrease light), then tweak that and worry less about the other stuff and most all algae issues.
Same thing told to me by Dave66 some time back. All very good advice, I would say.