What plants do you have?
I've had pretty good success with my plants. My 10 gallon has eco-complete (well worth upgrading IMO) and a 15 watt fluorescent bulb (1.5 wpg). I have java fern, dwarf sag, corkscrew val, java moss, amazon sword, and apons.
My java fern is tied to a piece of driftwood and grows like mad. I've gotten over 10 babies off of it since I bought it in March. My dwarf sag grows really well too.
For planted plants I think good substrate is key, for tied or floating plants I think lighting and water quality play a big part in it.
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