Watts per gallon

[DGK]

Hi people. I planted a 90 gallon aquarium and had it up and running for about 6 years. The plants are a Radican sword, amazon sword, crypts and java moss. I have 180 watts of light on it. The tank does very well and the plant look great. My question is I'm about to set up a 180 gallon aquarium. Since these tanks are pretty much the same height do I really have to increase the watts per gallon that much besides making up for some extra depth and width. I went with the 2 watt per gallon rule on the 90 gallon. If I did the same on the 180 we would be talking about 360 watts. I think my Discus would explode. Then I think about a little 15 gallon I have set up. It has a 15 watt Flora-gro bulb in it and the amazon sword I put in there is about to bust out of the tank. Any advise or sucessfull exp anyone has had trying different amounts on light on planted tanks please send my way. Thanks, DGK.

 

[Great Lakes]

DGK. I have over 500 watts above my 90 gallon..
It may seem a bit much, but works well. I would rather have too much, than not enough.

It would only make sense to double your wattage when doubling your volume. At least put four lights over it. You can always stagger the lighting cycles with timers too.

I have found you need to get to around ten watts per gallon to truly duplicate the suns intensity, so too much light is hard to achieve. We could get into spectrums and luxs, but it just starts to get confusing

GL