Return Plumbing

[Frostslasher]

Hi Folks,

First off, this is my first post here at RC, pleasure to be here. I'm in the process of building my first saltwater tank and have a few questions, or rather, looking for input on how I should design my return.

I have a 75 gallon Aqueon pre-drilled display tank (1.5" & 1.0" overflows). I'll be setting up the overflow using a gate-valved herbie system on the larger drain and the 1" as the emergency. They both return to a 20 gallon sump inside the tank, no fuge.

My question is, how should I go about plumbing the return? I have a Laguna Max-Flo 1500 with stand as a return pump. Headloss from the pump to the top of the display tank is approximately 52 inches. I'm leaning toward T splitting the return at the base of the DT and running a split return up each side to the corners. My thinking is because I have a powerful return pump, I should make use of it and get as much circulation/turnover to the DT as I can. If I split the return, how big should the PVC returns be, 3/4", 1/2"? Also, should I use schedule 40, or would 80 benefit by cutting down on noise from vibrations? I won't be using a refugium, so I may end up purchasing an algae scrubber if necessary and splitting the return to it (not sure if this would significantly affect my turnover to the DT).

It may be worth nothing that for corals I plan on using mostly LPS.

Any and all advice or suggestions is greatly appreciated!

<a href="http://imgur.com/F1vZmyP"><img src="http://i.imgur.com/F1vZmyP.jpg?1" alt="" title="Hosted by imgur.com" /></a>

<a href="http://imgur.com/6lJmBiF"><img src="http://i.imgur.com/6lJmBiF.jpg?1" title="Hosted by imgur.com" alt="" /></a>

(Return pump will go on right, along with 3 baffles)

[Fizz71]

I've never messed with schedule 80 so I won't speak to it...I've always used 40 and flex PVC which IMO is better than regular PVC to cut down on elbows.

Personally I like a slow sump, I prefer to use powerheads for circulation, not sump returns for a couple of reasons:
1. More flow, less dough (pumps are a lot more expensive than powerheads)
2. Long term costs - Big pumps cost more to run..a LOT more when you have to push long distances like I do.
3. Better control of direction - LocLine is nice, but still not as controllable as moving a power head.
4. Wavemaker capablities
5. Longer time for my water to recirculate through the skimmer.
...I could keep going. So anyway..IMO sump return pumps are just that...getting water back out of the sump. I don't use them for flow. I will tell you though.. philosophies vary both ways.

I also want to warn you on sump space...you're probably looking at about 6g of water in suspension when the tank is running..the faster the pump (depending on your overflow) the more water that will drain when the pump shuts off. You need to make sure your sump can hold that water on pump/power failure but also when it's running not require you to top-off 10 times a day to not run dry. I don't know if it's just the photo, but by the time you leave space for that skimmer and 3 baffles you're looking at a small last chamber so plan wisely when you put the baffles in there. Lower baffles mean more room for overflow water. Personally I'd go for a much wider sump.

Good luck.

[Phinnay]

Stick with 1" PVC, the only reason to use SCH80 for anything other than bulkheads / valves is if your piles of money are becoming a tripping hazard.

Make your runs as straight as possible and have a short length of flexible hose between the pump and your pipe, its crazy how much of a difference it makes for reducing vibration!

I like the idea of putting the returns in the corners, I did the same for my tank. You have the option of drilling the back and sticking some bulkheads in for the return OR you can have the pipe come up the back and over the top rim of the tank

Having a powerful pump is awesome, but you need to have a balance between the water being pumped into your DT and the water leaving it. If your overflow box / plumbing / whatever is too restrictive, your sump may run too low or you will have to throttle back the pump.

[Frostslasher]

Thanks for the feedback.

I think I'll take Fizz's advice and get a 30 gallon long sump instead and use the 20 as a quarantine, especially since I can fit a larger sump in the stand.

Instead of using a Max-flo 1500, I think I'm going to go with a 1350 to slow the turnover down a bit as well.