If you are asking by watts that`s a tough one because you just dont measure by watts anymore. Things like intensity and par have to be factored in. I`ll give you an answer but it`s only a guess. I`d say 3-5 watts per gallon would be my guess. If you were talking about lighting types I would say PC
`s and VHO
`s would be moderate lighting and T5`s and MH
`s would be in the high light range. Just some guesses on my part.