So are you going to plumb them together or not? I'm not sure that there would be any advantage from putting them together, especially if you're going in different directions with them, ie, one's going high light/high tech, the other less so.
For the 30g, I would think that a MH
would be overkill for basically anything FW
that you wanted to do with it. Yes, you probably could raise it quite a bit, or even run it right over the tank, but there's a serious question here about should
you. To me, it would unnecessarily complicate the tank, and will likely lead you to a frustrating and unnecessary series of algae/plant battles. A lesser lighting system might be warranted, and there are many good and economic alternatives available these days. Remember, in FW
, bigger is usually not better; it's just more complicated and subject to diminishing returns.
For the 220:
I am no longer worried about it because Im not going to keep much for plants in that tank Maybe just a couple big swords or something so the 4 t5hos should be fine for that.
This is probably the correct sentiment, although 4xT5HO is still a good amount of light for any tank. While the depth of the tank will markedly reduce light levels at the bottom, it's important to remember that swords are very tall plants, and the tops will be subjected to pretty high levels of light. I would say there's not much harm in trying with 4x bulbs, but be prepared to either reduce it to 2x or use some other method to reduce light.
Of course, if these is a decent fixture and these are quality reflectors as you often find on some SW
tanks, you might have problems regardless. Just something to keep in mind.