Plumbing on a 135G

[jsr]

Okay everyone, I know this has been asked and answered a million times. I posted this question on RC a while back and had too many opinions on what to do. Here is what I am looking to complete. I have a 135G Oceanic RR, dual overflow tank. I want to remove the standard drain hoses and replace them with PVC. My question is this...Would it be better, for flow and noise, to run each drain directly to the sump, or have them meet in the middle with a T fitting and then form a single drain into the sump? I have 1 inch drains from the tank and have dry fit the dual drain solution. I was thinking that having the two drain lines meet in the middle and having a 2 inch pipe going to the sump may be better. Any thoughts or suggestions? I have about 7 feet of the flexable PVC hose available as well (dual drain option). Sorry for the spelling errors.

[GKarshens]

I think I just read somewhere that (1) 2" pipe doesn't allow as much flow as (2) 1" pipes. That being said you may not need that much flow thru your sump.

[jsr]

Thanks Gabriel. I have already built the two drain setup and was leaning that way. My return pump is a nasty RIO 2500 so I am getting at most 500GPH through the sump. I agree that I want to keep that a little low so the skimmer and future fuge can do their work. I do plan on upgrading the return pump to an Ocean Runner 3500 when the wife gives me budget. That will put my overflow around 600 - 700GPH after head loss.

Not to change topic but have you tested the Red Sea salt?

James

[GKarshens]

Not yet. I was busy helping Karen last night and had a meeting tonight. I will try to do it tomorrow.

[jsr]

No worries. Take your time. It may be better to collect several salts and test out of the same batch of RO/DI.

Sorry for the off topic reply. Thanks again for testing the salt.

James

[Entropy]

Actually it is the other way around. A 2" pipe will flow more (close to 2400gph as a drain) than two 1" pipes (600gph each as drains), but in this case a single 2" pipe will only drain what the two 1 inch drains can provide (1200gph) when joined. So you would probably be fine just feeding both drains into a single line of the same size since you don't even have 600gph to begin with (unless you upgrade to more flow). Another idea might be to feed the skimmer and refuge off different lines (one each) so you can cater how much water each gets without effected the redundancy of having two drains. Regardless I would run seperate drains just for the redundancy (I should have signed up with NASA). If you combine them and a silly snail gets stuck in the main part you are setting yourself up for flood city. With two independent drains either one can handle all of your flow without the other. This of course is worst case scenario thinking.

I also have a 135g with dual overflows but both of my drains are 1.5 inch (single hole per overflow, no return). I am actually thinking of having all the flow in the tank go one way (to the right) and using the left overflow as a return by flooding the overflow chamber so it comes out of the teeth instead of in. Most of my flow will come from Koralia's.

[jsr]

Thanks Rich. I too have Koralia's providing most of the in-tank flow. I have one #4 right now and will be getting another #4 tomorrow. I dont have a fuge, yet. I am looking to change out my 29G sump with a 30G so its no so tight with the skimmer (Octopus NW200). I plan to drill a hole to join my new sump and an older acrilic tank (future fuge) together with a bulkhead. This is one reason I was thinking of the dual drain option.

[Entropy]

How do you like the Octopus? I need a skimmer now since my little Urchin is not going to cut it anymore.

[jsr]

I like it. You can’t beat the price at less than $200 shipped. The NW200 comes with the Ocean Runner 3500 pump which is quiet and cool. I keep my sump level about 8 inches and have the stand pipe as low as it can go and pull some nasty gunk from my tank. I have not done any mods but I hear you can mod the NW and dramatically increase the performance.

[tomanero]

If you intend to install two drains instead of one, the results of the calculator cannot simply be halved, because, for example, the cross-sectional area of two 1" pipes is only 1.57" while the area of one 2" pipe is 3.14." In other words, two 1" pipes cannot handle the same amount of water as one 2" pipe, and, in fact, will handle far less. The correct formula to convert the results of the drain calculator for use with two pipes would be: the diameter returned by the calculator is represented by the letter d. sqrt((((d / 2)^2 * pi) / 2) / pi) * 2, so a 2" pipe would equate to sqrt((((2 / 2) ^ 2 * pi) / 2) / pi) * 2 = 1.42". Rounding up, two 1.5" pipes could handle the same flow as one 2" pipe.

Ok, unless you are a math freak, you probably tuned out pretty quickly on the last paragraph. That's okay, there is a good rule of thumb that alleviates the need for the mathematics. All that needs to be done is to reduce one standard PVC size down from the results of the calculator and you should be safe. In other words, one 1.5" pipe could be replaced with two 1.25" pipes. Two 1" pipes could replace one 1.25" pipe. Even better would be to use two drains of the size recommended, which would allow one to be completely clogged, but the system could still handle the full flow without missing a beat.

Got this off the reefkeeping magazine website.

[jsr]

Yeah, the math killed me! Am I right in saying that if I do two 1 inch drains, I should be better off then joining the two drains with a T in the middle? My bulkheads are 1 inch out of the tank. All I have to do is glue the lines on.

[Entropy]

Independent drains will flow more than any other combo you have available and is the safest redundancy wise. It might not be the best sound wise (could be though), but it is the safest IMO.