Sump Size for 100 Gallon Tank and fitting into stand

[CJ Monty]

I am a proud owner of a new IM EXT 100 with the APS Stand. I am trying to figure out my sump situation for my APS stand. I really wanted to use a 40 breeder for my sump. Problem is the widest opening in the front (APS stand has one center brace that is off centered) is 27". I can not twist and turn the breeder to fit it through the opening. A 20 gallon long (30" long) I can fit through. I am worried a 20 long is not large enough as a sump. I faced with 3 options (maybe you can think of something else)

1. Use the 40 breeder. Remove the center support to add/remove sump. The structural integrity when the tank is full will be compromised. I could create to temp supports out of 2x4 and put them in towards then remove the center support.
2. Use the 20 long. Worried its not big enough.
3. Buy an expensive prefabed sump that will fit :-(

 

[Randomwhiteguy89]

I would say just go with the 20 long you don’t want to mess with the structural integrity of the stand, a 20 long should be big enough to put some hang on filter socks on one end and house a nice skimmer and have plenty of room for a fuge and return section, also to get more out of the 20 you can use bio bricks they can hold way more live bacteria then live rock.
the only issues with using a 20 long that you would have to consider are the fact that the return chamber where you will see the water level raise and lower will raise and lower faster since it is a smaller sump which can be fixed with an ato or just making sure that chamber is a bit bigger, and your going to need to make sure that if the power ever goes out that you either have reliable 1 way valves on all the lines going to the sump to avoid overflowing or that there is enough empty space left in the sump to hold what will drain into it without overflowing, personally I would take the 20 long and use all the precautions I listed above as it will still cost less than buying a prefabricated sump and work just as good

 

[CJ Monty]

I would say just go with the 20 long you don’t want to mess with the structural integrity of the stand, a 20 long should be big enough to put some hang on filter socks on one end and house a nice skimmer and have plenty of room for a fuge and return section, also to get more out of the 20 you can use bio bricks they can hold way more live bacteria then live rock.
the only issues with using a 20 long that you would have to consider are the fact that the return chamber where you will see the water level raise and lower will raise and lower faster since it is a smaller sump which can be fixed with an ato or just making sure that chamber is a bit bigger, and your going to need to make sure that if the power ever goes out that you either have reliable 1 way valves on all the lines going to the sump to avoid overflowing or that there is enough empty space left in the sump to hold what will drain into it without overflowing, personally I would take the 20 long and use all the precautions I listed above as it will still cost less than buying a prefabricated sump and work just as good

Thanks for the input. So I was going to actually be without baffles for this design. I use my apex and optical sensor to maintain constant water level. Good point on the backflow. I am not a fan of check valves. My understanding is there is about 6 gallons of back flow. If I run a the 20 at 7 inches it should have enough empty space to handle it but would need to test.

Good point of the bacteria. I have used marinepure in the past, was going to try out matrix this time around.

 

[Midrats]

I like my IM EXT tank. One thing I don't like is the height at which the return hole is drilled. They should have gone at least half an inch higher. One must rely on the position of the Loc Line to determine the amount of water that back-siphons into the sump. I have the flared nozzle near the surface, but the actual hole is much lower, so don't bump it and hope no one else moves it. Loc Line isn't water tight either so if the links become less snug from adjustment and you have a long power outage potentially more water could drain into the sump. If you removed the Loc Line the water would drain all the way to the bottom of the return bulkhead, which is a significant amount of water. The Loc Line seems to be holding up thus far but the potential is there. I've considered replacing it with some street elbows to form a more reliable, and higher water-tight seal.

 

[CJ Monty]

I like my IM EXT tank. One thing I don't like is the height at which the return hole is drilled. They should have gone at least half an inch higher. One must rely on the position of the Loc Line to determine the amount of water that back-siphons into the sump. I have the flared nozzle near the surface, but the actual hole is much lower, so don't bump it and hope no one else moves it. Loc Line isn't water tight either so if the links become less snug from adjustment and you have a long power outage potentially more water could drain into the sump. If you removed the Loc Line the water would drain all the way to the bottom of the return bulkhead, which is a significant amount of water. The Loc Line seems to be holding up thus far but the potential is there. I've considered replacing it with some street elbows to form a more reliable, and higher water-tight seal.

Street elbow where on the inside of the tank?

 

[Midrats]

Yes, two actually. One screwed into the return bulkhead with the opening facing up, and another screwed into that one with the opening facing forward. That would form a higher, immovable water-tight seal. I wouldn't use the Loc Line so the siphon would break immediately when the return shut off. I have a 20g sump on a 50 EXT I just set up and was surprised by how much water back-siphons even with the return nozzle right at the surface.

 

[CJ Monty]

Yes, two actually. One screwed into the return bulkhead with the opening facing up, and another screwed into that one with the opening facing forward. That would form a higher, immovable water-tight seal. I wouldn't use the Loc Line so the siphon would break immediately when the return shut off. I have a 20g sump on a 50 EXT I just set up and was surprised by how much water back-siphons even with the return nozzle right at the surface.

How much water do you think back siphons on your 100 ext?

 

[Midrats]

Length x width x height divided by 233. So measure from about a half an inch up from the teeth on the weir, which is about where the water level will be when the tank is running, down to the bottom of the hole of the return bulkhead. Plug that distance in as the height and that will give you a pretty good estimate.

When I go home at lunch I'll do some math and let you know.

 

[CJ Monty]

Length x width x height divided by 233. So measure from about a half an inch up from the teeth on the weir, which is about where the water level will be when the tank is running, down to the bottom of the hole of the return bulkhead. Plug that distance in as the height and that will give you a pretty good estimate.

When I go home at lunch I'll do some math and let you know.

Thanks didnt know what the water level would be. Yikes that is 10g.

 

[CJ Monty]

@squareriggersailor do you use the aps stand? what sump you have for your 100 ext?

 

[Midrats]

I have the 50 EXT and yes I use the APS stand. That won't be 10g for you if you position the output near the surface, 10g is just the potential. That's why the bendy Loc Line makes me a little nervous. I was at my LFS not too long ago and they were cleaning up a flood because someone adjusted the return nozzle.

 

[HeyJay]

Why not use a standard 29 gallon tank for the sump?

 

[CJ Monty]

Why not use a standard 29 gallon tank for the sump?

That is what I use on my current setup. I agree if the overflow is as much as it seems to be that is a great option. The drawback is the aps stand comes with a shelf that spans the entire inside of the stand (which is really nice). Using the 29 vs 20 would cause me to raise the shelf 6 inches (which cuts the shelf space in half). But that is highly preferable over a wet floor

 

[Midrats]

With the nozzle right at the surface 2g drains into the sump when I kill the pump. If it were to drain to the bottom of the return bulkhead it would be about 5g. This is on the 50 EXT mind you, so your calculation seems accurate.

 

[CJ Monty]

With the nozzle right at the surface 2g drains into the sump when I kill the pump. If it were to drain to the bottom of the return bulkhead it would be about 5g. This is on the 50 EXT mind you, so your calculation seems accurate.

Sounds good thanks for the info.

 

[spacey]

Just get a good check valve and you should be good 99% of the time. Putting street elbows on the inside will cut your flow so depending on how much loss you already have due to the height and other elbows it may be a pyrrhic victory . I got the Fiji Cube 36 for the sump and 10 Gal is nothing for it to catch even if it came down to it. The standard run-time level is at roughly 20 Gal, which is less than 50% fill. I measured and it can absorb a 20 Gal drain event.