you could always make one cheap enough if your inclined enough to do so, but
wouldn't jump to more than another 15watts or so.. keeping your watts per
gallon near 2WPG is good in your case, 30watts in a 20gallon is 1.5WPG

you might be able to swap your 15watter to an 18 and make a 2x18 hood,
giving you 36watts, or 1.8WPG, which is good....


"Phil Williamson" wrote in message
...
I have a 20 gallon tank with a few live plants in it now that are growing
slowly since I only have 15watts of lighting on the tank.. How much would
i
need to get my plants to grow at a reasonable rate? Also, is it worth
building a DIY light system or is it just best to buy a new hood and duel
light stripe?

Phil..