ready to upgrade lighting - have some questions...

T5s would be less to run, true. But don't rule it out. I never understood the shimmer everyone talked about until I got mine. I'd think you'd get away with only one unit and a 175 watt would give you some flexibility in your tank.
 
Yes,but if you are going to spend the $,Get the MH system.No Worries then,If you are concerned with the heat,put a $10 fan on it.
 
You don't need to follow the watts per gallon, as it is just a guide and not really accurate when you start factoring T5s into the mix. Sincerely, a GOOD T5 is the next best to MHs, some say they are as good or better if the shimmer isn't important.
 
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