Sump volume question . . .

[LostAngeles32]

Hello all,

I am new poster here, but have been reading for some time. I have been a freshwater aquarist for a while and my girlfriend's reef tank has taunted me for the last time!

I am in the early stages of going reef, and I have some ideas about what I would like to do, and I have a question regarding Sump size.

I know that the "biggest you can" standard answer, but I am curious about the realities of how big it needs to be.

I am looking at getting a 125 gallon aquarium that measures 48"w x 24"h x 27"d which is about 31,104 cu in. (which really makes the tank 134.64 gallon, but with overflows etc)

So, if the bottom an overflow entry is 2" -3" inches from the top of the tank and the tank was actually "full" that would mean that between 11.22gal - 16.83gal would flush out of the tank at any given time (assume normal operation here), right?

So, if I actually went for 10x tank volume for gph flow (1250 gph), how much water is actually run through the sump/refugium?

What would be the minimum or the natural maximum? how do I safely compute backflow for a power outage?

Sorry for the long-winded question, I would just rather figure this out before I had Lake Moron in my living room!

Thanks for the thoughts!

p.s. - I am looking at having a set of double display refugiums setup above the sump, but below the main tank, but I will get into that in a future post

 

[jer77]

The amount of water that drains when the power goes out is determined by how low the overflow teeth or return exit is into the water, whichever is lower. People also poke holes into the return piping to prevent too much water from draining back. Also people usually have a durso pipe in place which prevents all the water in the overflow from draining out. So your calculations are probably correct, so allow for this much water to drain back into your sump.

About the size of the sump, go for the largest size that can fit under your stand. The amount of water that runs through the sump depends on head loss. It really should depend on the skimmer's pump size. So i the skimmer's pump is 1000gph then your return pump should closely follow this size after head loss. You can have more or less if you want more or less flow through your sump or going back into your tank, but it will be less efficient from a filtration point a view.

Oh,
[welcome]

 

[trrack2far]

""""''So, if I actually went for 10x tank volume for gph flow (1250 gph), how much water is actually run through the sump/refugium?"""""

Just something I noticed in your question...

typically the filter circulation of the tank - sump/ fuge - and returned to the display tank is about 3 to 5 x volume an hour.

Dispaly tank circulation (with powerheads in the Display) is minimum recommended 10x/ hr.

If you are considering keeping corals that require high flow, you would want to bump the Display circulation up to maybe even 20x an hour.

Its been my experience that if you try to 'overkill' the filter circulation much more than about 5x an hour, you end up with microbubbles that are caused from sooo much water draining from the tank into the sump.

As for the size sump you should use,,,,of course the biggest is the the best. For the 125g, you should do ok with 40 ish and up.

 

[jeeperrs]

I have a 120 that is 48 inches as well. The biggest I could fit under the stand was a 40 breeder. I decided to run the overflow close to the max, so I am running a mag 12. I did a DIY sump. The drain pipes flow into a bubble box that is located in the refugium which is the first section, the second section is for my skimmer and heater, and the third section is for my return pump. My refugium is only macro algae and rock, I don't have any sand in it. I have zero micro bubbles that make it to my display tank with this set-up. I will say that running the overflow this fast will result in a little more noise, I honestly don't notice it. The worst thing is that I had to place an extra piece of glass over the top of the refugium and bubble box because all the bubbles from the drain would have eventually caused a lot of salt creep. With the glass over the top all the water from the popping air bubbles is caught and that was my only issue

 

[LostAngeles32]

Thank you all for your replies.

I was guessing around 40 gallon sump was where I wanted to be.

Soon I will post my "rough tank sketch" and welcome any thoughts . . .

 

[LostAngeles32]

<a href=showthread.php?s=&postid=10421999#post10421999 target=_blank>Originally posted</a> by trrack2far

typically the filter circulation of the tank - sump/ fuge - and returned to the display tank is about 3 to 5 x volume an hour.

Dispaly tank circulation (with powerheads in the Display) is minimum recommended 10x/ hr.

Thanks for the info, BTW

 

[an411]

Jeepers I second that On the size of the sump that is what I am currently using for my 120. I have done tests and unplugged everything to test and see if during a power outage I would be fine and I passed with no water ending up on the floor. Good luck also if you need ideas for sump design there are some good diagrams in the reef central gallery on the home page.

 

[INCEPTION7]

I would go with at least a 40 gallon sump, as the others have said. I would go for at least double the amount of flow that you are talking about. Remember, I am talking about in tank volume flow, not through filtration flow. So a 1250 Gal/Hr return pump plus a Tunze would be fine. To make sure your sump won't overflow during an outage, all you have to do is start with a low water level in your sump and then turn the pumps off. Add more water as needed.

 

[LostAngeles32]

Thanks for the advice!

I have moved this discussion into my bigger tank thread HERE