HOB Overflow Question

[kkirkt]

I have a 125 gallon that I'd love to switch to a sump (instead of a canister). However, I keep my water level about 6 inches lower than the top of the tank (I have mudskippers and they need some room above water).

Is there a ready made HOB overflow that is big enough (or can be set up for) a water level 6 inches below the top? I have surfed the web and not found (or recognized) what I'm looking for.

Thanks,
kevin


Side notes:
Obviousy, my tank is not drilled and quite frankly, I'm too much of a coward to drill my 125 (especially since it's already set up and I don't want to move everything for the time drilling and plumbing would take)

Since I have ~100 gallons in my 125, I assume that's a decent safety margin for risks of overflow if I do something wrong (clogged overflow). I've considered a switch in the sump so if water level drops too low the return pump would stop (and I'd want a siphon break, etc)

 

[kkirkt]

After some more internet surfing, I'm tentatively planning on building a DIY overflow. I don't think it will be quite as attractive, but hopefully it won't be too bad.

Now my dilemma is figuring to find the largest sump that can fit in my stand . . .

 

[Oughtsix]

Yep a DIY hang on overflow should work.

Have you considered drilling the tank for an overflow?

 

[kkirkt]

I thought about drilling (very briefly), but since the tank is set up . . . . Breaking it down completely so it's light enough to move, then having the time to carefully drill, having space fro my stock in other tanks . . . . Not worth the risk (messing up the tank) and hassle to me. If I were starting from scratch I'd prefer one already drilled. And maybe I'd have the guts to try drilling it myself.

 

[duanes]

I have drilled tanks while they were set up with fish in them.
Just take the water level down a few inches below where your intended surface height would be.
Thick tanks of over 100 gallons or more, are (IMO) easier to drill than small ones. The only tanks that cracked for me while drilling were a 55 and a 20 gal (my fault for rushing, or placing the hole too close to the tank rim), my over 100 gal tanks all were easy.
I make an appropriately size wooden template to hold the drill bit steady, use plenty of water from a hose to cool the diamond bit, and go slow with even pressure.
I use a basic hand drill. Its so easy I wish I'd done it 30 years ago, would have saved a ton of money on overflow boxes, and countless on the floor spills from DIY overflow piping that lost siphon.
I've drilled at least 8 tanks with the same diamond bit.

 

[kkirkt]

Just the idea of moving 1000+ pounds (aquarium, water, rocks) to give me enough room to drill hurts my back. Of course I could drop the water way down, but still it would be several hundred pounds. I remember my wife, neighbor, and I had fun moving the empty aquarium . . .

I know once I have the tank drilled I'll be happy I did it, but I'm a coward.

 

[Oughtsix]

I have also drilled tanks in place after lowering the water level without ever having any issues. The hardest part by far is working up the courage to just do it!

I understand where you are coming from... A flood from a lost siphon is what finally pushed me over the edge to just do it! I drilled one from the inside to the outside.