Overflow box question

Hi guys

I bought a couple of 2nd hand tanks, they have built in overflow boxes. This is the first tanks that i have with overflow boxes in.

My question is this:

If water comes in on the one side of the tank, and the overflow is on the other side of the tank, does the water mix sufficiently? My concern is that new water just flow on the top over and out the box?

Please give your comments. My previous tanks had overflows which the inlet is in mid level in the tanks

 

So I came up with a plan:

O bottom feeding overflow: Will also form stage 1 of my mechanical filtration

 

You'll need to watch out for what happens with a power outage - having the intake of the overflow so low means the water will siphon out until it gets to that level. So you'll need to have a pretty big sump with lots of overflow space, and scape the tank so any plants will not be exposed.

A better solution might be to setup a wavemaker to ensure the water circulates adequately and there is enough circulation at the substrate level to pick up any muck. Even setting up the return from the sump to move water around rather than sending it along the surface would work. Alternatively, a small hole in the overflow close to the water surface to help break the siphon might work

 

No, the original overflow box stays in place, water cannot drop below that level in the event of a power outage. Water moves up between the 2 boxes. so once input stop, overflow stops. Not closed at the top.

 

If your outlet sponge gets clogged with leaves can it still overflow?

You could also attach a spray bar or one of those flexible tube things to your inlet to direct the in-flow appropriately.

Flexible Aquarium Tank Plastic Water Outlet Duckbill Nozzle Pipe End 20mm - 2/Pack https://www.amazon.com/dp/B07T4KLT2D/ref=cm_sw_r_cp_api_glt_fabc_JPFD2Q5NMFMZ2C7JQHZM

 

Yes, the outer box is higher than the first, but still lower than my tank level. so if the sponge gets clogged, the outer box overflows (also indicating to me that the sponge is clogged.

Thanks for your input guys!

 

Ah, right, misinterpreted your drawing then. All looks good then I'm curious to see how it works out