internal overflow plumbing setup - 55 gal with small internal overflow box

[cjdesign]

Hi Reefers, I'm planning a new drain system on my 55 gal saltwater/acrylic tank. Upgrading my external cpr overflow box with an internal version (6.25 x 5 x 4). Wondering what the best drain type is for my size and set-up. I have enough room for two 1" bulkheads within the overflow box. Seems Herbie setups are mostly mounted at the bottom within tall overflow boxes, I will be drilling out of the back and I only have 5" total clearance. The bean animal uses 3 drains - so that's out of the question. Thanks in advance for any advice you my have.

 

[RocketEngineer]

Did the 55g come with the holes already drilled? I ask because most 55g tanks can't be drilled as they are made with tempered glass.

 

[cjdesign]

Thanks! Fortunately mine is acrylic.

Just came back from my local shop and he agreed the two drain system is ok with 90 up and 90 down for my setup. He was mostly concerned with the capacity of the sump and it's ability to hold back flow. I have a tall sump and fill to half capacity so i'm ok. He offered this equation to calculate how much water is back flowed into the sump during power outage: L x W x (H - water height) divided by .231? Also the drains can be placed side by side without haven't to offset the height.

 

[SGT_York]

A herbie will work fine. just place the holes as deep as possible to avoid the vortex pulling air into the siphon.

 

[uncleof6]

Really? Herbie is a modification to fit in a corner overflow.

Two pipe siphon system, out the back of an internal overflow: Done the right way...

 

[cjdesign]

this is ok for a 6.25 x 5 deep box? thanks!

 

[cjdesign]

A herbie will work fine. just place the holes as deep as possible to avoid the vortex pulling air into the siphon.

I thought I'd drill 2" from the top for the bulkheads and adding the 90 down would add another inch or so.

 

[uncleof6]

this is ok for a 6.25 x 5 deep box? thanks!

Unfortunately, since this is an archived design, and my archiving for stuff done for RC, is somewhat haphazard, I cannot locate the original skp for this design. However, I am very consistant, therefore can give critical dimensions.

The top of the weir, is 1" below the "euro-brace". The holes are centered 2 3/4" below the euro-brace. The plumbing (for the drain) is 1". The water level in the overflow, is 1" below the top of the weir. From that you should be able to "guesstimate" the size of the overflow... using dims from real 1" plumbing fittings. You would want 3/4" + below the bottom of the downturned elbow, to the bottom of the box.

It is to your advantage, to build the box the full length of the back of the tank. Therefore the box dimensions: length of tank x 5"w x 6.25h would work well. Using the dimensions you mentioned in your original post is pretty much a waste in terms of actual performance in the system. Using 4"w by 5"h would *probably* work, but 6.25" of length is useless. It is a long discussion. In terms of "custom" building things, there is no point to making them inefficient, and using ideas that are modified for use in tanks that are already poorly designed.

Read the side bar...for a primer to the discussion..."surface renewal"

http://www.beananimal.com/projects/silent-and-fail-safe-aquarium-overflow-system.aspx

 

[SGT_York]

Uncle,

Anyone using a C2C and not using a full three pipe bean animal I'd have to question their sanity.

A herbie is a simple concept with a durso pipe and a siphon, you can put them anywhere you want.

CJ,

Adding a Coast to Coast is certainly a great idea and you won't regret it. It's is suprisingly easier than it appears as well. I highly recommend you go that route.

If you insist on going with your existing overflow are these the dimensions?
6.25 Long, 5" wide and 4" tall?

If so just measure before you drill so the downturned 90 is 1/4" above the bottom.

 

[cjdesign]

6.25 Long, 5" wide and 4" tall?

this is the overflow box size.

 

[cjdesign]

Adding a Coast to Coast is certainly a great idea and you won't regret it. It's is suprisingly easier than it appears as well. I highly recommend you go that route.

coast to coast is not an option due to cost to make and size. this would take up a great deal of space in my tank. If my tank had more width maybe.

 

[cjdesign]

I can buy these sizes. I can go with the larger 18" box but didn't think my tank could handle this size.

RSS07 - 5 1/4" L x 3 5/8" W x 5 1/4"H (Up to 60 gallon tank)
RSS12 - 7 1/4" L x 4" W x 5 1/4" H (Up to 120 gallon tank)
RSS18 - 12 1/2" L x 4" W x 5 1/4" H (Up to 200 gallon tank)
RSS24 - 18 5/8" x 4" W x 5 1/4" H (Up to 300 gallon tank)

 

[cjdesign]

Read the side bar...for a primer to the discussion..."surface renewal"

http://www.beananimal.com/projects/silent-and-fail-safe-aquarium-overflow-system.aspx

thanks!

 

[cjdesign]

Unfortunately, since this is an archived design, and my archiving for stuff done for RC, is somewhat haphazard, I cannot locate the original skp for this design. However, I am very consistant, therefore can give critical dimensions.

The top of the weir, is 1" below the "euro-brace". The holes are centered 2 3/4" below the euro-brace. The plumbing (for the drain) is 1". The water level in the overflow, is 1" below the top of the weir. From that you should be able to "guesstimate" the size of the overflow... using dims from real 1" plumbing fittings. You would want 3/4" + below the bottom of the downturned elbow, to the bottom of the box.

It is to your advantage, to build the box the full length of the back of the tank. Therefore the box dimensions: length of tank x 5"w x 6.25h would work well. Using the dimensions you mentioned in your original post is pretty much a waste in terms of actual performance in the system. Using 4"w by 5"h would *probably* work, but 6.25" of length is useless. It is a long discussion. In terms of "custom" building things, there is no point to making them inefficient, and using ideas that are modified for use in tanks that are already poorly designed.

Read the side bar...for a primer to the discussion..."surface renewal"

http://www.beananimal.com/projects/silent-and-fail-safe-aquarium-overflow-system.aspx

Thanks Uncle for your precise explanation and guidance. I will be purchasing the 18.5" box and will run drains as your 3d illustration shows. My acrylic tank is only 13" wide and has a large center brace, installing a bigger box would be damn near impossible.

 

[cjdesign]

Update:

I've finished the setup and need some additional guidance on dialing in the main drain. Thanks again for your input and recommendations. The system works great and is very quiet!!

but....When the system loses power- that's another story.
The main drain has a siphon break. On restart, the water level rises up to the emergency drain and with cap screwed on the drain doesn't have enough airflow/water exchange to flow properly and will eventually flood. When I unscrew the emergency drain cap, the water has more air and starts to work but the main pipe never recovers.

My questions are:
1. Should I drill a hole in the top of the emergency cap?
2. How do I stop the original siphon break on the main drain.
3. What is the proper level of the overflow box compared to the upside down 90.

Thanks in advance.

 

[uncleof6]

Thanks Uncle for your precise explanation and guidance. I will be purchasing the 18.5" box and will run drains as your 3d illustration shows. My acrylic tank is only 13" wide and has a large center brace, installing a bigger box would be damn near impossible.

Nothing is **** near impossible, it is willing to or not willing to... Well drilling tempered glass is, and setting up a drain system that works as it should, based on some of the advice I see around here, is also darn near impossible. Space taken up by a coast to coast overflow is useless space anyway.

You set it up wrong? There is not supposed to be any water in the emergency any time...except during startup. If your system fails to restart, there is a problem with the main siphon. Water rises and flows in the emergency, until the air is purged from the siphon. If it cannot purge the air, the system will not start. (very well anyway.) Water flow in the emergency is not any measure of performance, and as I said, there should not be any except during startup. You need to go back through the proper set up, detail by detail. Start with how deep the drain line outlets are in the sump.

When the system stops, there is no way to maintain the "siphon." Because the system operates on head pressure, the siphon does not need to be maintained, in order to restart. If somehow it was maintained, the tank would drain...

 

[cjdesign]

Nothing is **** near impossible, it is willing to or not willing to... Well drilling tempered glass is, and setting up a drain system that works as it should, based on some of the advice I see around here, is also darn near impossible. Space taken up by a coast to coast overflow is useless space anyway.

You set it up wrong? There is not supposed to be any water in the emergency any time...except during startup. If your system fails to restart, there is a problem with the main siphon. Water rises and flows in the emergency, until the air is purged from the siphon. If it cannot purge the air, the system will not start. (very well anyway.) Water flow in the emergency is not any measure of performance, and as I said, there should not be any except during startup. You need to go back through the proper set up, detail by detail. Start with how deep the drain line outlets are in the sump.

When the system stops, there is no way to maintain the "siphon." Because the system operates on head pressure, the siphon does not need to be maintained, in order to restart. If somehow it was maintained, the tank would drain...

You hit the nail on the head - I think it's the drain line depth. it's 5 inches below the water line and should only be 1-2 below. I will retrofit today and test. Thanks again!!

 

[uncleof6]

You hit the nail on the head - I think it's the drain line depth. it's 5 inches below the water line and should only be 1-2 below. I will retrofit today and test. Thanks again!!

ummm NO!! <= 1" (That means less than or equal to 1") 2" is too deep.

 

[cjdesign]

ummm NO!! <= 1" (That means less than or equal to 1") 2" is too deep.

1.75 below works great!! I can cut shorter but this seems to work fine.

 

[uncleof6]

1.75 below works great!! I can cut shorter but this seems to work fine.

Cut them off at or less than 1". As with most things, it works fine now, but down the road it won't...