How high to mount MH's and do I need actinics

[spy231]

Guys, I am setting up a 30 gallon tank that will have mostly sps in it at 2 rbta that I have. I hope they find a place to settle down and stay put. I also have a 20L frag tank sitting right next to it (about 5 inches apart) on a custom stand I built.
The frag tank is going to have a plenum in it so it will only have about 8 inches of water in it and when I put the rack in it the frags will be about 5-6 inches from the surface. The 30 gallon will be bare bottom. I bought 2 250 watt MH units to hang from the ceiling. How high would you mount them?
Also, do I need to add some actinics and how would you do that? I have 3 T5 ballast that I will not be using, but the MH lights I got are just a retrofit system so I dont know how I would make it look good by adding T5's to it.
Any suggestions?

 

[scsinet]

Those are big lights for those tanks, so I'd mount them up at least 14". That will ensure that you don't heat the water excessively.
You do not need actinics. They are for human eyes more than anything else, so if you like actinics, great, but the well-being of the animals do not mandate them.

 

[brettd]

Actinics do seem to help in the propagation of coraline algae and I have some corals that open up more when I added a second pair of actinic T5s. They also will give your tank a much better look on your colorful corals. I feel they're necessary for the added beauty of your tank alone not to mention the algae growth.

 

[rgf1046]

I wouldn't get too excited about the actinics. When I upgraded to 15K XM bulbs for my MH's, they casted a blue tint that brought out the colors of the coral beautifully, and in my opinion, negated the need for actinics.

 

[spy231]

Thanks guys.
I will mount them that high and make them adjustable.
I just posted about how to add actinics, but if you dont think I need them I might wait to see what it looks like without them and then go from there.
What type of bulbs would you put over each tank? I dont guess the frag tank would need to look good. Just promote growth. Right?

 

[rgf1046]

Originally Posted by spy231
http:///forum/post/2506813
Thanks guys.
I will mount them that high and make them adjustable.
I just posted about how to add actinics, but if you dont think I need them I might wait to see what it looks like without them and then go from there.
What type of bulbs would you put over each tank? I dont guess the frag tank would need to look good. Just promote growth. Right?
Exactly. If you want to bring out colors in your DT, then I would try a 14 or 15k, to give you a little blue, and bring out colors. I found out there is a lot of variation in color and quality between 15k bulbs, so look around at some of the comparison pictures on this site of the different brands so you're not disappointed with the color. It's a lot of money to potentially spend on trial and error.