No need for CO2? They claim it.

i think co2 reduces algae because it increases plant growth thus outcompeting algae. The exception is BBA which seems to melt from co2 injections (need + excel == goodtimes)

Excel shouldn't be melting annnnnnny plants imo.

When you first start dosing it a plant might 'ripple' like it was irritated but they get used to it very fast.

If you have more questions about Excel i'd recommend posting on a the SeaChem forum at plantgeeks.com -- They are sponsored by SeaChem and trained people answer questiosn on that forum all day long.
 
By the way, I've been spot-treating some black beard algae with Excel (applying with a syringe, straight to the tufts) and it's killing it. The stuff is turning red, and getting softer! Hooray :D
 
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