Questions regarding a variation of the BeanAnimal Overflow
 

I am going to be setting up a 125 gallon Mezzo tank soon and would like to incorporate the Beananimal design. The mezzo tank already comes with an internal overflow in the middle with a 1 1/4" hole at the bottom. I would like to use the 1 1/4" hole in the bottom as my Siphon Standpipe and would like to drill two additional holes from the rear into the overflow to act as the Emergency Standpipe and Open Channel Standpipe. Since my hole drilling from the rear will be permanent, I want to make sure they are in the correct location. I have included three images below that show what I am talking about. Could someone please give me some feedback. Thank you.

The size of the hole u are drilling will affect how far down from the top of the tank u need to drill the hole. Basically u want to be atleast 1 times the hole size from the top edge of the glass & u want to keep the same amount of distance inbetween holes. If u drill a 1.25” hole u want to be a minimum of 1.25” from the top edge of the glass to the top of the hole. It can be more, but no less. If u want to use the existing hole for the syphon then I would stay pretty close to the minimum. So if u are drilling a 1.25” hole I would drill the holes at 1.25” from the top of the glass to the top of the hole. U can go a extra 1/4” or so but I wouldn’t go any lower then that because the hieght of the open channel will determine where u want to keep the water level inside the overflow box. If it is to low u will have a waterfall entering the overflow box & it would be noisy.

I would consider using the existing hole for the open channel & the new holes for the syphon & emergency. For one the existing hole should have a straight shot to the sump which will help keep the open channel quiet, which in turn will keep the hole system quiet. Another reason is so u can have options on the hieght of the open channel. If u have options u can play with the hieght to get it as quiet as possible. If u use one of the holes in the back for the open channel then the open channel will be at whatever hieght u drill the holes & u will have no adjustment.

I did this on a past tank and it worked fine; just be certain that the back panel is not tempered. Also, when you say 1 1/4' hole, do you mean that is the size of the actual hole or the size bulkhead that it will accept? If the former, that's pretty small (1/2' bulkhead).

Thank you for the feedback. The hole sizes are to fit a 1 1/4" bulkhead fitting. Also, is it possible for me to gain some flexibility by having the holes on the back of the aquarium drilled quite a bit farther down and control the internal height of the siphon and emergency overflow with an upturned elbow and length of pipe to position at the perfect height inside the overflow? Thank you,

Greg

Hello Simon, I see you are on the forum. The hole sizes are to fit a 1 1/4" bulkhead fitting. Also, is it possible for me to gain some flexibility by having the holes on the back of the aquarium drilled quite a bit farther down and control the internal height of the siphon and emergency overflow with an upturned elbow and length of pipe to position at the perfect height inside the overflow? Thank you,

Hello Lsufan. I am not exactly sure how to navigate around in Reef Central and would like to ask some specific questions about the beananimal design. Is it possible for me to get your email so I can send you the same tank pictures and ask some specific questions I have. Since I will be drilling two holes in the back of the tank, I want to make absolutely sure I put them in the right spot. my email is gregr@dynamicsolutionsusa.com. Thank you for any help you can provide.

I drilled my holes quite low in the overflow wall and used elbow and PVC pipe lengths to get to the right height inside the weir.