How much Flourish Excel should I be using daily for a 20 gallon tank?
None! Unless you're using it to spot treat algae
Why is that?
Excel is glutaraldehyde. It is a biocide. Long term use is harmful to both plants and fish. Do not use!
The dose on the bottle says 1 cap (5mL) for every 50 gallons, so for a 20 gallon it's 2 mL.
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