Tank to Sump Size Ratio

[codemannc]

Is there a rule of thumb on a sump size to tank ratio. I am considering setting up a 150 to 210 gallon reef tank and I was wandering if there was a general rule of thumb on a suggested sump size? Example 4:1 120 gallon tank would need a minimum 30 gallon sump.

[Reefmedic79]

I don't think there are any rules, one large enough to fit all your minimum required equipment; skimmer, heater, pumps and one that you have the space for. I personally would go for the biggest one you can fit in the available space.

[Steve175]

Mine is 1:4. Bigger is better.

[DrBegalke]

I would go as big as the available space allows.

[ssick92]

Well your example is misleading. a 4:1 Sump to tank ratio would mean a 120g sump for a 30g tank. Just thought I'd let you know haha Steve 175 has it right

Anyway, I always say bigger is better. More water volume typically = less maintenence to ensure good water quality. And make sure it can fit all your equipment needs.

[codemannc]

oops! Sorry folks, don't know what I was thinking, 1:4 is the correct ratio for my example.
Thanks for the input.

[FUA]

I agree with the above folks, bigger is better since a larger volume of water will remain more stable.

[Wildisme02]

Check out UrauJoey on YouTube. He explains everything as far as sump sizes and how to drill and plumb everything.

[dixiedog]

5,000 gallons if possible.

[SC Reefaholic]

There is a connection between the two. The smaller your sump, the faster water will move through it so the less time your heater and skimmer have contact with the water. This is based on any given return pump. It is important to size your sump and return pump correctly so that you get the most efficiency out of your heater, skimmer, etc.

That being said, I dont know what the best ratio is. Based on my experience, the best I have found is a sump 25% the size of my display with a return pump that is turning my display over 4 times per hour. Skimmer seems to pull the most waste at that rate and heater/chiller appear to be operating the most efficient.

Many people try to use a high power return pump to create flow in their tank but that just pushes water through their sump too fast and lessens the efficiency of the equipment in there. This could be offset with a larger sump to some extent.

IMO its best to size your return and sump correctly and use other methods (Powerheads or Closed Loop) to create flow in the display.

[brob22]

50 gallon tank 75 gallon sump dfilledall the way up over here

[The Punisher]

I don't think there is any rule of thumb that holds for all tanks. I would suggest getting one as big as possible, and keep in mind back flow from power outages as well.

[MarineSniper]

Another consideration is how much volume it will hold, based on how much your tank will lose in a power outage, plus the volume you already have in the sump for regular use

If your tank will drain 2 inches of water before your skimmer box, or whatever, stops the flow; your tank needs to have that space available to absorb it and not dump the excess all over your floor. In the case, the dimensions of your sump will be as important as the volume capacity

[reefermad619]

I always like to size my sumps at 1/3 of the DT size.

[geaux xman]

a standard 75g usually works out well for a ~200g tank. it fits nicely inside the stand, easily fits a large size skimmer, and you can get them used for about $75-100.

100-120g display tanks, the 40g breeders makes for a good sump.

[billdogg]

My system is a 150DT, 120 fuge, and a 50g sump. It is just barely big enough. Because it and the fuge sit in a seperate rom behind the DT, I am thinking of a way to increase the total sump volume - probably by plumbing in another - if the wife will let me, it will be a 100g rubbermaid tub. Bigger is better, pretty much without exception.

[allsps40]

I always go wit the largest sump I can fit under my stand. Go as big as you can with a sump, more water volume means better stability.

[gveng]

i don't necessarily think their is a rule of thumb, but i think you should have a plan of action before setting a sump.

for me, it always comes down to what skimmer i buy and the foot print it has, from there i can start deciding on the tank size to accommodate it.

[BigFOWLR]

I didn't see it mentioned but you also want to have a sump big enough to hold the overflow from your DT in case the power goes out.

Usually that is 1-2" of water from your DT. So calculate that surface area and make sure the sump can handle that much more water.

[CRC88]

Originally Posted by SC Reefaholic

There is a connection between the two. The smaller your sump, the faster water will move through it so the less time your heater and skimmer have contact with the water. This is based on any given return pump. It is important to size your sump and return pump correctly so that you get the most efficiency out of your heater, skimmer, etc.

...

Many people try to use a high power return pump to create flow in their tank but that just pushes water through their sump too fast and lessens the efficiency of the equipment in there. This could be offset with a larger sump to some extent.

This isn't quite right. The water "moves" through your sump at a given rate based on your return pump. If you choose a smaller sump, the water will appear to move through it faster because you can see more turbulence and it will make the trip end to end faster because there's a shorter distance to go.

However, the speed at which the water moves through your sump has no effect on the equipment. The heater will put X amount of energy (heat) into your water regardless of how quickly it moves through. Same with the skimmer, that skimmer pump will pump the same fixed amount of water into the body of the skimmer where the actual filtration occurs regardless of how quickly the water is moving past the opening.

The only time you'll need to worry about the speed of the water moving through your sump is if you plan on putting baffles in to reduce microbubbles in your DT from your skimmer. If the speed (flow) is too high, you'll need to make the baffle spacing thicker than the "standard" one inch. This will allow the water to move slower through the baffles, and allow more time for the bubbles to rise to the surface out of the water column. If the flow through the baffles is too fast, then the bubbles won't have time to rise out of the water and you'll see more microbubbles in your DT.

Originally Posted by MarineSniper

Another consideration is how much volume it will hold, based on how much your tank will lose in a power outage, plus the volume you already have in the sump for regular use

If your tank will drain 2 inches of water before your skimmer box, or whatever, stops the flow; your tank needs to have that space available to absorb it and not dump the excess all over your floor. In the case, the dimensions of your sump will be as important as the volume capacity

This is spot on. When figuring out my sump size, my biggest consideration was how much water it would have to hold in case of a power outage to avoid a flood. To figure this out, I looked at my DT and determined how many inches of water would drain out of it before the siphon broke. In my 55g DT, it was about 3g of water. But considering I only have a 10g sump, then I could only run my sump at about 2/3rds full during normal operation. A 10g is 12 inches high, so I made my baffles 8 inches high. This means it would run at 2/3rds full, and would be able to hold 3.3 gallons in case of an overflow.

In a 120g or 150g, every inch of water column height = 5.2 gallons of water.
In a 180g or 210g, every inch of water column height = 7.0 gallons of water.

This means that if 2 inches of water drain before a siphon breaks, you'd have 10.4 or 14.0 gallons of water that needs to go into your sump to prevent an overflow depending on your tank size. This means if you use a 30g sump, you'd only be able to put the baffles halfway up the height in order to accommodate a 14g overflow. If this is a little confusing, get a piece of graph paper and make a scale drawing of your intended capacities. This will help you get an exact amount.

But for what's been said, I agree on the "Bigger is Better" idea. More volume = more stable water chemistry.

[LoneRanger]

I almost have a 2:1 with my display (a bit over 300 gallons) and my sump is a 125. I wish I had a larger sump. I like most was constrained by space. The better way would be to have a 300+ gallon sump and a "measly" 125-150 gallon display.

L.R.

[codemannc]

Wow. Thanks guys for useful insight. I first thought this post was going to be kind of silly. Now I'm glad I asked the question. I had completely forgotten about sizing the sump for power outage overflow!

[Bielaz]

Do you need a sump for a nano with sps or is it unnecessary?
30" 12" 18"
L. W. H
Many thanks