[tang daddy]

I have not personally used them but would think that the spread might be alittle streched for 1 every 2 ft. A member on here was running some par 38 over his nano sps awhile back, imisky Eugene might have more personal experience over spread. Also mounting them higher up may blind the other members of your house and I guess if you were to space them a few ft apart it would most definately have some dark areas inbetween.

You may want look into running a cheaper led fixture for the fowler, btw what is the length and width of the tank these led will be put on?