Plumbing Concern

[Matt0676]

Hello,

I am in the process of buying a used 180g tank and am concerned about the size of the drains/returns. The seller informed me that the drains are 1" and the returns are 3/4". There are two of each. Are these too small? The return pump is a little giant 4-MDQX. Thanks!

Matt

[uclamatthew]

That does seem a bit small for a 180 gal tank...
http://www.dursostandpipes.com/faq/41-what-flow-rates-are-possible-with-a-durso-standpipe (Flow Rates)

Even with two of them, that's maxing out at ~1200 gph... for reference, my 125 gal has a single 1.5" (for ~1500 gph).

[drparker]

That sounds like standard AGA overflows

[Matt0676]

That does seem a bit small for a 180 gal tank...
http://www.dursostandpipes.com/faq/41-what-flow-rates-are-possible-with-a-durso-standpipe (Flow Rates)

Even with two of them, that's maxing out at ~1200 gph... for reference, my 125 gal has a single 1.5" (for ~1500 gph).

Sorry, that link didn't work.

[Matt0676]

That sounds like standard AGA overflows

Is it possible to re-drill those same holes to make them larger?

[Chiefsurfer]

^no. I mean MAYBE with the right glass-driller, but generally no.

The flow depends on what size sump you want to have. If you have a 40-gallon sump, 1200gph is almost 30x flow. Most will say that they want 10x flow through the sump. SOOOOO, it CAN be fine on something like a 50-75 gallon sump. It can also be VERY low if you go with something like a 180 gallon sump. I'd say you're fine if there are 2 of them.

[drparker]

Is it possible to re-drill those same holes to make them larger?

Not usually, the bottom of a lot of AGA tanks are tempered.

You should be fine since most of your flow should be with powerheads and/or closed loops. As long as your flow through the sump provides enough gph for your skimmer you'll be fine. I think you want about 1.5x to 2x the flow rate of your skimmer.

I would target 1000gph flow your overflows, yes a 1 inch hole can do 600gph but that does not take into account loss due to build-up in the pipes or plumping head loss.

[Fizz71]

+1 on pretty much everything said in here.

You shouldn't need more than what you have for sump flow. Yes a stronger pump could out perform your drains and maybe even the skimmer teeth depending how many inches of it you have...but it's a moot point because you don't need more. For more flow go with powerheads..I avoid closed loops now because they take way too much electricity, produce too much heat and setting up drains and plumbing you can clean is a PITA..power heads have seriously improved in the last 3 years and are you best option for more flow IMO.

[Matt0676]

^no. I mean MAYBE with the right glass-driller, but generally no.

The flow depends on what size sump you want to have. If you have a 40-gallon sump, 1200gph is almost 30x flow. Most will say that they want 10x flow through the sump. SOOOOO, it CAN be fine on something like a 50-75 gallon sump. It can also be VERY low if you go with something like a 180 gallon sump. I'd say you're fine if there are 2 of them.

From what I gather (haven't actually picked the tank up yet), the sump is about 40 gallons with a separate 20 gallon refugium. So based on 1000gph that equates to about 16.6x flow through the sump, that should be acceptable right?

The tank also comes with Four Koralia 4's. That should also help things shouldn't it?

[Matt0676]

+1 on pretty much everything said in here.

You shouldn't need more than what you have for sump flow. Yes a stronger pump could out perform your drains and maybe even the skimmer teeth depending how many inches of it you have...but it's a moot point because you don't need more. For more flow go with powerheads..I avoid closed loops now because they take way too much electricity, produce too much heat and setting up drains and plumbing you can clean is a PITA..power heads have seriously improved in the last 3 years and are you best option for more flow IMO.

Do you think that the four Koralia 4's will be enough to offset the narrow plumbing?

[Fizz71]

Do you think that the four Koralia 4's will be enough to offset the narrow plumbing?

It all depends on what you want to keep, how you set it up and who you listen to on tank turnover. :) My initial goal for my 240g mixed reef tank was 40x, however with the open setup I have my single Koralia Mag 8 at 3250gph along with a 600gph return speed is only 16x on paper, but I get such tornado whirwind of water that any more and I wouldn't be able to keep my sand down (which is already a problem). But that is 100% because of my peninsula setup and open rock work so don't for a second read that as "16x is all you need".

I have seen people shoot for 100x on a SPS dominatated tank and I've seen people happy with 20x or less (me included). Figure out what your return ACTUALLY gets after head and friction loss along with the 4800gph you'll get from 4 koralia 4s and see what you get for total turnover and see if you're happy with it. The only way you'll know if you don't have enough is if you large well established SPSs start to RTN on you in the middle. :( IMO 40x should be your goal for now.

[tank o tang]

Use all 4 holes for drains and bring your return up and over the back.

[Chiefsurfer]

I agree with Fizz, anywhere in the 40x neighborhood should be quite good for a starting point. If you have 2 1" drains, you have a possible 1200gph drainage. You definitely will have some head-loss, so I would shoot for ROUGHLY a 1200gph pump. Most-likely, with a little head-loss, that should bring you down between 1000 and 1100. That will also give you some slow-down/drainage loss allowance for growth, snails, etc.

Add that to 4800 from the K4's, and thats about 6000gph. Divide that by 180 gallons(you calculate turnover for corals using your DT volume only) and get roughly 33x turnover. That will give you a starting place. If it comes down to it you could sell off the 2 K4's, and get 2 K5's, and that would help. BUT, 33% is fine to get started.

Oh also, the 16x is fine for turnover in your refugium.

[Matt0676]

Use all 4 holes for drains and bring your return up and over the back.

Great idea!!! I never even thought of that (newbie syndrome)! I may try that!

[Matt0676]

I agree with Fizz, anywhere in the 40x neighborhood should be quite good for a starting point. If you have 2 1" drains, you have a possible 1200gph drainage. You definitely will have some head-loss, so I would shoot for ROUGHLY a 1200gph pump. Most-likely, with a little head-loss, that should bring you down between 1000 and 1100. That will also give you some slow-down/drainage loss allowance for growth, snails, etc.

Add that to 4800 from the K4's, and thats about 6000gph. Divide that by 180 gallons(you calculate turnover for corals using your DT volume only) and get roughly 33x turnover. That will give you a starting place. If it comes down to it you could sell off the 2 K4's, and get 2 K5's, and that would help. BUT, 33% is fine to get started.

Oh also, the 16x is fine for turnover in your refugium.

Thanks Chief, I appreciate your (and everyone else's) advice. I am sure the flow is decent as the tank has been established without any problems for quite some time now. The pictures show excellent corals so I am going to keep my fingers crossed. I am picking it up this weekend and plan on really evaluating the plumbing. Luckily the drains have shut-offs so I can fill with RO/DI and salt while working on the plumbing.