Sump refugium design question

[JoeGnall]

So i'm drawing out my refugium design that came to me last night. 55 gallon 48x12x20. Setup kinda like this... Means i would have 28.9 gallons in at all times, and give me 13.6 gallons of room in case of power failure drain off. Also return will have siphon break holes drilled, and be a shutoff on main drain branch before splitting to a dual bulk head.

[Reefmedic79]

What is your question?

[JoeGnall]

Lol sorry did it on my way out. Questions should be.

A. Is my calculations right for the gallin capicities per say each zone (which they aren't i divided by 271 instead of 231)

B. Would under this design, be appropriate enough for drainback in case of power failure( even going with the security of a ball valve on the drain)

C. Thinking 1 1/2" main drain bulkheading into two 3/4" drains feeding sump section that run down to 3.5" off of the base of the sump, to help quiet it and reduce micro bubbles which lead to question d

D. What is the flow rate for a 1 1/2" drain. I'm thinking inside corner over flow, and having 4 drilled returns to a 1/2" bulkhead with adjustable lines to help with flow it the DT which is a 90 gallon.

I can't really find accurate flow rates or i'm just using wrong questioning when using the google machine.

[Reefmedic79]

A. I didn't do the math, but I wouldn't worry to much about the volume of water in your sump. I'd aim for half or a little more than half full total. You basically just need enough water for your skimmer to operate properly and your return pump doesn't pull air when it's running.

B. Don't put any type of valve on the drain line from the tank. You don't want to restrict the drain in any way. Leaving half the sump volume for drainback is usually enough, that and making sure you return line has a siphon break built into it, or don't have the outlet to your returns to deep in the tank.

C. I don't think I follow, you want to split the 1.5" drain into 2 3/4' pipes? Why?

D. I think a 1" overflow can handle approx. 350gph, you'll want at minimum twice that for a 90G display, IMO.

[JoeGnall]

Ok, that clears up most of my concerns and questions. Why the split not sure, thinking in crease pressure keeps bad junk suspended longer.

Flows are the thing thats kicking me in the tail. I understand the principals and want to move as much as you can as quickly as you can. But the numbers elude me. Like want to cycle at minimum two times the volume if not 3-4 especially for a reef system.

But how it gets down, then back up correctly send my head into refried bean brain farts.

[Reefmedic79]

If you have the means. I would go with 2 1" overflows for the tank which means these overflow can handle approx. 700gph. Have them run as straight as possible to the left side of the sump. Don't join them and use as few elbows and couplings as possible. Having the pipes submerged in the sump will help with the noise as you stated.

Next choose a return pump, you want one that gets you as close to 700 gph, accounting for head pressure, as you can. You want to plumb it with the same diameter pipes as the outlet of the pump, usually 3/4", and you don't want it to decrease in diameter until the last moment, usually right at the return nozzle in your tank. If you sump is directly below your tank, in your stand, then you probably looking at around 5' of head pressure, not accounting for elbows, ball valves or any other coupling you have plumbed.

The above suggestions will put you around 10x the water volume through your sump, taking into account lost water volume due to displacement, once LR and sand are in your tank.

Now when it come to turnover in your tank in relation to care for your corals. i.e. LPS prefer 15-30x's tank volume, I don't use the return pump in this calculation. I only use the amount of flow put out by my powerheads.

For example in my tank approx. 30G total volume, and my powerheads are capable to run 3000gph or 100x's my total volume, but I have them dialed down to about 75% and on reef crest mode which makes the flow variable. I like this kinda of flow because my tank is/will be an SPS dominated tank.

[JoeGnall]

Thank you so much Reefmedic, this was exactly what i was looking for, and was the missing piece i just couldn't figure out.

I'll now be able to finish working on the stand and rest of plumbing. The last is just my reactors and i'm feeding them via return and plumbing the returns of them directly into the DT that would be the correct way I'm assuming

[Reefmedic79]

That sounds good, just make sure to account for the added loss of head pressure when you split the return off for the reactors.