Lighting

[phishyphil]

My tank currently runs T5 lighting and i am wondering on the optimal wattage to put in to promote healthy plant growth and avoid green water.

Planted
No CO2
T5 lighting.

Am i correct in sating it will need 1/2 Watts of light per 1 litre of water when using T5?

Also how manu hours per day?

 

[Rynofasho]

I'd try to get at least 50 watts over it for 9 hours a day. It's all relative really. You can try it for 8 for a few weeks and see how they look and adjust as needed. I had a 36W T5 light on my 36 gallon tank and still saw pretty good growth with about 10 hours a day of light. This is assuming you purchase low light plants such as anubias, crypts, java ferns, moss, pennywort, etc.

Considering the availability of 36" T5 fixtures and most of them have 2 39W bulbs, I'd say you'd be pretty safe doing that, again, with lowish light plants.