Help on overflow and sumps mechanism

[fr3n0z]

Hi guys, got a 64Lt nano AIO, want to add a small 20liter DIY sump. I will drill it and add a blau aquaristik internal overflow.

I am having trouble on understand if and how i can control the level of water in the display. Since sump is small is necessary that not much water flow back when return is off. Can the water outflow not be completely submerged? if so, how do i control that? With a ball valve? And in that case, any risk it will be more noisy?

Hope you can get what i mean by the "sketch" because is quite hard to me to explain it.

 

[KrisReef]

An adjustable pump allows you to ramp up or down the return flow to balance circulation between the aquarium and the sump. The rest you seem to understand, and in my experience the only way to figure this out is to build it and run it. Then you will know if your pump is too small or too big, which is why an adjustable pump provides a way to build, operate, and adjust.

I have an adjustable pump on my skimmer, makes life much easier. HTH.

 

[RocketEngineer]

So, basics:

Set the water level in the WHOLE SYSTEM first. To do this, I fill the display until the water starts flowing to the sump. Then I fill the sump until it’s about 1-2” below overflowing. Pumps are off the entire time.

Now that the volume is set, turn on the pump but watch. If the display tries to overflow, cut back on the flow from the pump. If the sump drains before flows, the sump is too small (rare). Because you only have one drain, you can’t control that. Once the system is running, mark the water level on the sump with everything on as well as everything off. These are for topping off and doing water changes.

 

[fr3n0z]

So, basics:

Set the water level in the WHOLE SYSTEM first. To do this, I fill the display until the water starts flowing to the sump. Then I fill the sump until it’s about 1-2” below overflowing. Pumps are off the entire time.

Now that the volume is set, turn on the pump but watch. If the display tries to overflow, cut back on the flow from the pump. If the sump drains before flows, the sump is too small (rare). Because you only have one drain, you can’t control that. Once the system is running, mark the water level on the sump with everything on as well as everything off. These are for topping off and doing water changes.ù

ok, that's clear. What i wonder now is:
Since water level will be at lowest point of overflow, when i turn on i suppose sump will empty a little, i am wondering now if sump will empty too much and skimmer will not skim anymore since is too high. But i think that i will only see when i will run it. At worst, i will buy a 10g tank and make a bigger sump.

Or i try to find a way to keep skimmer chamber always high and regulate the rest of the sump height so that i have enough safety in case of return failure.

 

[\m/reefsnmetal\m/]

If you're worried about the return turning off and syphoning enough water to flood your sump, then drill a hole in the plastic return nozzle. If you do this at or just below the normal DT water level then the hole will break the syphon and prevent flooding. I do this with my tanks and it has worked every time my power went out. Just make sure to take a tooth brush or something and clean the hole every now and then or it will clog and not work as intended.

 

[fr3n0z]

If you're worried about the return turning off and syphoning enough water to flood your sump, then drill a hole in the plastic return nozzle. If you do this at or just below the normal DT water level then the hole will break the syphon and prevent flooding. I do this with my tanks and it has worked every time my power went out. Just make sure to take a tooth brush or something and clean the hole every now and then or it will clog and not work as intended.

return is higher than overflow hole so i'm not really worried about that (and i can put a anti-return valve) i am worried that as in "sketch" when return is off, water will lower to the lowest part of overflow hole and all that watre could overfill the sump. My skimmer in order to work need to be filled around 3/4cm from the tank rim, making it quite full compared to sump i've seen in videos where water is always at about half or a bit more.

 

[\m/reefsnmetal\m/]

return is higher than overflow hole so i'm not really worried about that (and i can put a anti-return valve) i am worried that as in "sketch" when return is off, water will lower to the lowest part of overflow hole and all that watre could overfill the sump. My skimmer in order to work need to be filled around 3/4cm from the tank rim, making it quite full compared to sump i've seen in videos where water is always at about half or a bit more.

Oh gotcha, my bad I misread your question. In that case, I would recommend a taller sump if possible.

 

[RocketEngineer]

ok, that's clear. What i wonder now is:
Since water level will be at lowest point of overflow, when i turn on i suppose sump will empty a little, i am wondering now if sump will empty too much and skimmer will not skim anymore since is too high. But i think that i will only see when i will run it. At worst, i will buy a 10g tank and make a bigger sump.

Or i try to find a way to keep skimmer chamber always high and regulate the rest of the sump height so that i have enough safety in case of return failure.

The baffles set the water height in each chamber. When doing that initial fill, the water should be over the baffles. It is this water above the baffles that ends up in the plumbing and in the display while the pump is on. If the pump outlet is near the water surface when running, it will pull in air and empty before the water in the display makes its way through the drain into the sump. What you call return failure is a common state of my systems when doing water changes. If designed correctly, having the return off does nothing but fill the sump up to that 1-2” level.

 

[RocketEngineer]

This sump shows the water levels while running. When the pump was off, the water filled the sump to just under the black trim.

 

[RocketEngineer]

And do NOT use a check valve. They don’t work in a reef environment because things like sponges or crustations can grow on the sealing surface and totally negate them. No matter how well maintained, they are too prone to failure to trust. Avoid, and design the system so they are not needed.