You sir, delivered it. In the words of Buzz Lightyear, “To infinity and beyond!”
After reading your response I decided to not use metal halides. I didn’t know that the ponies would be that sensitive to bright lighting. So I’ll switch to a (2 tube) 4 foot long 6500K T-5 bulb fixture and 1 or 2 96 watt power compact bulb/s for actinic lighting to simulate dawn and dusk. The lighting will be sufficient enough for macro algae and maybe some low light tolerating leather corals and mushrooms.
My thought on the design of the seahorse habit and the filtration has changed. I’ll now build a pvc pipe type of waterfall on the opposite side of the overflow with a jet output before an adjustable ball valve. I think the rock work will now be adjusted to create high, medium and high flow areas. I did not know that the mustangs like to swim in a bit of strong current every now and then.
I will definitely put that protein skimmer in right after the return to the sump.
Thank you again. Your e-mail will definitely be a resource and I’ll send future sea horse owners to http://www.seahorse.com .