Sump size

[pontiac2002gtp]

What size sump should you have for a 350 gallon or so tank?

[JoeAyers]

IMO as big as your space will allow and still allow you to easily work in it.  At a minimum you will need to figure out how much water will drain out of your tank when the power shuts off and then go up from there.

[Joel]

I don't think that there is one right or perfect answer to this question. There are multiple variables that are going to need to be considered first. Is this just going to be a recovery sump or will it be used as the main filtration system? What will be in the sump and how much space will these apparatus take up (protein skimmer, filter pads / socks, pumps, return inlets etc.) What is the surface area of the display tank? How far will the sump be from the display tank? Both of these need to be considered to determine how much recovery the sump will be able to handle when the pumps are turned off. Just because you have "X" amount of gallons does not mean you all ways will need "X" amount of recovery in your sump. For example, If you have a standard 75, 90 or 110 gallon aquarium with the 48 x18 foot print the amount of water that back flows into your sump will be approximately the same. The consideration as to recovery in your sump is mostly going to be determined by how many inches of water will back flow out of the tank and into your sump when the pump is turned off. In this example, if each tank drained 2" of water into the sump, that volume of water would be the same even though they are different gallon aquariums. (48" x 18" x 2" is the same volume of water regardless of what the total gallon of the aquarium is)

What I do to determine what is the minimum size sump I am going to need is first check what the operating water level in the tank is and then what the approximate water level would be with the pump off. Lets use the 48" x 18" foot print as an example. If the water level dropped 2" that would be approx 7.5 gallons of water that back flowed into the sump. (48" x 18" x 2" = 1728 / 231 = 7.48 gallons) Take into consideration approximately how much water is in the lines as well. Next take into account what size sump you want to have, what it's operating level will be and weather or not it will accommodate the volume of water that will back flow into it when the pump is turned off. Now this is mostly a safety factor to determine so you won't have any floods and does not take into consideration filtration needs. That's a whole 'nother ball game.

Give a little more information about what your needs are and what the display tanks type is (reef / fish, etc..) what the tanks dimentions are, what type / style  of pre filter, etc and I bet we can get a more accurate answer to the question. I agree with Joe's opinion that bigger is typically better but I also know that we normally have space limitations to deal with too. Post some more info and see what we can come up with...Joel

[pontiac2002gtp]

The tank is 94h30h32w and im basically going to have to get everything just wondering what it is going to cost me.  I have 2 icecap 660 and a solar 1000lw dimmer im going to use till i can get some metal halides.  Im going to have to build up my equipment over time.  i have a 90 gallon now i was thinking of trying to use for the sump.

[Joel]

The tank is 94h30h32w and im basically going to have to get everything just wondering what it is going to cost me.  I have 2 icecap 660 and a solar 1000lw dimmer im going to use till i can get some metal halides.  Im going to have to build up my equipment over time.  i have a 90 gallon now i was thinking of trying to use for the sump.

A 94 x30x32 is more like 390 gallons.

I'm going to assume that this is going to be a reef tank. And again, assuming that this sump is going to be used as a filtration system, the smallest sump I would use is a 125 but only if I was using an external protein skimmer and external return pumps. Although a 90 gallon may be able to recover the water from that size aquarium, in my opinion, it does not have enough area to properly filter that size aquarium (again, assuming that it is going to be a reef tank). You didn't indicate how much area you have for a sump but many people use larger rubbermaid tubs for recovery sumps and filtration system. With out much more detailed information, it's tough to give a good answer.

Where did you get this tank?

[pontiac2002gtp]

http://www.reefcentral.com/forums/showthread.php?s=&threadid=1241338&perpage=25&pagenumber=1
Heres a link to the tank tell me what you think about it.  I did the calculator and came up with the 390 gallons too then i thought about the thickness of acylic and when you subtract that you get the 360.  Should i be worried about the metal brace installed on top will it be a problem with different expansion rates?  I would like to try to keep as much of the equipment as possible under the tank but i can run some stuff through the wall and put it in the laundry room but i don't like it being so close to all the chemicals.
What do you think it will cost me to get this tank up and running?
Thanks for all you help.

[Viggen]

I think that is the tank I looked at a whila ago.  If it is I would STAY AWAY from it.  I beleive the owner wanted a acrylic tank with a more open lid so he cut out most of the top more like a euro braced tank.  He then made (or had it made) a metal frame around the top to help reinforce the tank.  I talked to a friend who works with acrylic & installs large tanks for a few manufacturers & he told me that rarely do tanks stay together that are modified this way. He stated usually they will break in time.  It's a great deal on a tank but I think the reason it's such a great deal is due to it being modified in a unsafe way thus nobody wants it. 

[pontiac2002gtp]

Could the tank be made safe again if it broke that would be real bad.  How much do you think repairs would cost if possible?

[Bwlr]

You could DIY.
You might be able to find a replacement top brace for it.
Just remover the one he cut, and then silcone the new one back on.

The tank has to be empty to do this.




-edit-
Sorry... didn't know it was an acrylic tank. Just kinda skimmed through the posts before mine.

[Viggen]

When I looked at this tank I sent pics to my friend in Columbus who builds acrylic filters & installs tanks for a few aquarium manufacturers.  He told me the best/safest way to fix the tank was to remove the metal fram & glue a new top on top of the existing top.  That would give the best/safest fix, he told me to not buy it due to other tanks popping up f/s.  Unfortunantly I missed a 300g for $500 by a few hrs.... oops......