want to have a planted tank- what do I need?

That would come out to 1 watt per gallon which is on the low side but that doesn't mean you can't grow plants. You just have to be careful about what plants you pick. I have 2 low light planted tanks that I love because they are easy to care for and very inexpensive. For a low light tank you would want to stick to anubias, certian crypts, java ferns and some of the mosses. There are other plants out there that do well in low light but you will have to do some research. If you bump your lighting up to 2 watts per gallon you will get a much broader selection of plants but you will start to need to add co2 and dose fertilizers on a regular basis and trimming becomes a regular thing too. Its really just depends on how much you are willing to put into the process and how much money you want to spend.
 
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