[toddnbecka]

I'll be picking up a slightly used light: http://www.thatpetplace.com/pet/product/productInfo.web?&infoParam.itemKey=204873 , also included are 2 extra 50/50 bulbs. What will this be good for growing w/out CO2? I'm planning to place it on a 30 long shrimp and dwarf crayfish tank. Current plants are java moss & ferns, Najas, and duckweed running amok. Substrate is a thin layer of gravel mixed with crushed coral to maintain pH and hardness for the inverts. Filtration is 2 air-driven double sponge filters.

 

[hooha]

Link doesn't work....but assuming it's not 3+watts per gallon, that should be more than enough light for the current plants in there. You could probably use a regular NO strip light for java ferns and moss (and najas).

 

[toddnbecka]

I fixed the link, actually should be around 4-4.5 w/g total. The Najas is growing with the current lighting, but not as compactly as I'd like. The current setup is 3 separate strip lights, 2 are 30", 1 is 24". Doesn't look good with the 24" light in front of the strip lights.

 

[hooha]

There will likely be algae issues with that much light and no CO2. But then again, it is a cherry shrimp tank

I suspect if you want the najas to grow more compactly, the problem is more likely increasing the CO2 to match you lighting rather than more lighting though.

 

[ianiwane]

I would not get that light if you have no intentions of running CO2. You are just asking for problems. That is way too much light for a 30g tank w/o CO2.