I'd use 1" personally.

Hey Myka, one thing to consider is the heat generated by the PS3. I have one as a return pump, I love it by the way as it's supper quiet, but it does create a large amount of heat. I'm pretty sure my heater hasn't come on in 3 years. Even in the winter I'm constantly battleing over-heating issues.

Have you considered a spray bar to eliminate the deadspots? A little old school I know but I put one in awhile back when I was on a DIY kick and I've been very happy with it. If setup right it can be hidden quite well... Just my 2 cents...

Mark told me your leaving for Saskatchewan :cry:... When are you going?

I still don't get it, I have a 50 gallon tank with a single 1/2" return pushing around 300-400gph and all my LPS and soft corals have done very well. Recently put 6 clams in there as well which are all doing just fine. Tanks been running for almost 3 years which no problems. You're still going to get dead spots with a closed loop, but dead spots aren't going to kill your reef. LPS corals don't like lots of flow, you're going to do more harm and good. Plus extra heat, noise, potential leaks, clutter, maintenance, and less space in the stand.

http://i11.photobucket.com/albums/a1...r1_06_2008.jpg

Myka, in my 45g, I built a closed loop and hid the pump inside the overflow. That way, no external drilling was required. My CL pump is a Pentair Quietone 3000. It works great that way. I made a PVC pipe "ring" around the top of the tank for the Loc-Line nozzles. But, I needed more flow. I too had alot of detritus settling. Added a Koralia 2 and all is great now. So, in my 45g I have a Mag 3.5 Sump return, Quietone 3000 Closed loop and K2 powerhead.

I am very worried about the heat created by the PS3. I have heard they are horrible for that. The tank is also going to have 2x 250w MH over it and 2 x39w T5s for actinics. I'm worried about the lighting being a bit too intense for my LPS, but they are mogul run on electronic ballasts so shouldn't have too high of a PAR reading and if all else fails I can pick bulbs with lower PAR rating, just a waste of electricity.

I'm not sure what to do about the tank...I would really like to try out a closed loop. I know the Little Giant pump I have isn't supposed to leak much heat at all because of it's bypass type design. Maybe I should sell the PS3, and buy a more appropriate pump for my tank. I originally bought the PS3 for my 75g return, but plans have changed for that tank.

Yes, I'm moving to Saskatoon next Friday. =] I will have to come back for the tanks though.

Whatcha gonna do with the 75???

Well I found a nice canopy for my 40g, so I will stick to keeping that one for my reef, otherwise I was thisclose to setting up the 75g for my reef. So I'm gonna put plants and Dwarf Cichlids in the 75g I think.

Ok, so I sold the 40 and the 75 in BC, and bought a 90 out here in Saskatchewan. So, I'm thinking I will do a small 2-way closed loop on this tank for three reasons:

~ So I can hopefully eliminate most if not all powerheads.

~ T the pump outlet for an easy water change system like superduperwesman did in his nano contest tank. It won't work in the sump because there will only be about 3-5 gallons of water in with the pump. Will a ball valve seal well enough to have no leaks on the bare end when not doing a water change?

~ To get random flow/waves. So I can get away with probably just using one VorTech (later on down the road when I feel rich again) and not have to use two to get a wave action, or maybe I will be happy just using a couple Koralia 4's or some such thing.

So...any input on how many gph I should run my closed loop? Remember I keep LPS only, although I will add a few SPS to the 90 (I think). Pump recommendations? The OM 2-way wants to use a bypass unit if more than 1000 gph is going through it, which from my understanding pretty much defeats the purpose of using a pump with more than 1000 gph. Or should I use a SCWD which will deplete the gph by about 30%?

myka: I was thinking of buying a SCWD You say that it takes 30% of the total gph?
Thats not very good.

I have used both the OM products and SCWD, and I would not hesitate spending a little more on the OM product, and the bypass can be used for feeding a refugium, reactors, etc.