please help w/recs for 4000gal+ tank

[Cabreradavid]

Hello. This is quite an undertaking, I hope it works out for you. I am new to the board and just thought I would provide what comments I can. I finished graduate school a year ago with a degree in Marine Biology. My research involved Atlantic Stingrays (D. sabina) and as a result I maintained a 3500 gallon stingray tank and several “smaller” 150-500 gallon tanks. It’s not exactly a reef tank, but I would be happy to discuss my experience with you. Briefly, It is a fiberglass round tank with a filtration system that I and a fellow graduate student built (after numerous discussions with Aquaria and the South Carolina DNR aquiculture group). Here are some quick thoughts: What exactly do you have in mind for the schematics of the filtration/water movement system (i.e. what’s in the sump)? I am not certain how applicable my filtration system would be as my experience slants more towards fish than corals…but basically it consisted of gravity return of water through pipes located near the bottom of the tank to a large pre-filter containing gravel and floss media to a pump that drives the water and injects O2 (by allowing a small amount of air through a valve in the PVC tubing) upwards through a very large fluidized bio-bead media cylinder (unlike a trickle filter, water flows up through the media, a fast flow rate assures proper oxygenation). Water return is through a PVC pipe angled to assure circular movement of water. I can discuss in more detail if you are interested. With regard to pump choice, I like pool and Jacuzzi pumps (inexpensive, durable, and easy to replace). I like Hayward pumps personally (very dependable). We didn’t have to worry too much about high protein, so we made foam fractionators out of PVC, and powered them with airline tubing from a ¼ Hp air pump (I think)…but you would probably like more than that for yourinverts. A good place to look for pumps etc. is Grainger (they have stores all over the east coast at least), as they carry the more industrial size stuff. I don’t know if any of this helps, hopefully it does. Let me know if you have any questions/want to bounce ideas off. Also…this might be a no brainer, but make sure there is adequate surface area of sand for the stingray to move about (otherwise they develop sores).