Is this a good source of light?

the thing is acient tho? where could i find a replacement.

home depot has a shit load of bulbs to choose from look at the yard buster 200 watt replacement 15.00 bucks but its a cfl ? your choice
good luck

MH or metalarc bulbs don't work in my mercury fixtures/ballasts, (tried a few) is there a conversion? Not that my MV fixtures don't make fat buds, it would be nice to use metalarc, that's all.

on that im not sure but if you search the web you can get an mv to hps conversion for about 50 bucks good luck

I'll stick with MV, $50 will buy 3-4 coated MV bulbs, or 2 more MV fixtures with bulbs. Either way my floro and mv setup works quite well, compared to my first few done with just floros.

good luck let us know how ya do