Hi,
I'm trying to figure out what is a good MH bulb for the long run. I have a 50g tank and thinking about putting in a new MH bulb. I currently have only 2x55 (50/50) PCs. In the future, I plan to try to keep some clams. I was debating between the Ushios 10K, XM 10K and XM 20K. I like the...