Too much light for a non CO2 tank?

[Ethoxide]

After alot of thought and research I have decided to try my hand at a planted tank. I was planning on doing a non CO2 enriched tank so i was aiming for around 2 watts per gallon of light. I purchased 2x39 watt T5HO fixture to go over my 46 gallon bowfront giving me around 1.7 wpg. I know that T5s are quite a bit more powerful than other flourescent bulbs, but I didn't realize how powerful until i switched them on.

Now I am not adverse to making a yeast CO2 source, but spending hundreds of dollars on pressureized CO2 isn't really an option for me right now. Are either of these neccessary for me or am I just working myself up for nothing?

 

[Gerryd]

Well many folks have non-c02 tanks and they work very well, but they usually use less light. Based on your type of fixture, it is possible you can use just one of the bulbs, based on the spread of the remaining bulb. Or you can DIY to raise and lower the lights as needed.

BTW, it should not cost 'hundreds' for pressurized c02. Many welding supplies may sell used 5 and 10 lb cylinders for much less than a shiny new aluminum one. Plus, you can build a nice reactor for < $15. Your big cost is a good regulator setup, but e-bay or swaps for used setups are also an option.

You may want to research this a bit before you decide one way or the other....