Overflowbox work?

[Andrés Garza]

> I have noticed that many aquarists express concerns about hang-on external overflow boxes. I would like to know whether these systems are truly reliable or if there is a significant risk of failure associated with their operation. I am seriously considering avoiding drilling my aquarium and using one of these overflow boxes instead. Could those with experience using them please share how they have performed in the long term, and whether you have encountered any issues?

 

[kfisc]

I used an overflow on a 40 gallon for many years (the life of the tank) without issue. I'd much rather have an external overflow than the risks associated with drilling a tank, especially if you have no prior experience drilling glass. A key is to have an overflow box large enough and adjusted in very good sync with your return rate.

 

[wvned]

They work really well until they don't. There is a reason we take the risk of drilling tanks. I have done several now. A corded drill, slow speed, light pressure and flowing water on the bit.
Small tanks/ thin glass is more difficult than larger tanks with thicker glass. Glass bits grind a hole. They do not cut like twist drill bits.

 

[griss]

They work really well until they don't. There is a reason we take the risk of drilling tanks. I have done several now. A corded drill, slow speed, light pressure and flowing water on the bit.
Small tanks/ thin glass is more difficult than larger tanks with thicker glass. Glass bits grind a hole. They do not cut like twist drill bits.

Yep, I’ve drilled several tanks over the years as well.

Many moons ago, I had a U-Tube HOB overflow. It lost siphon almost daily. I pilled a hole in the top, connected airline tubing and connected the other end of the tube to the powerhead air intake. It still lost siphon about once a week or two.

 

[wvned]

I had one on the 75 when I moved it here. It ran flawlessly until we got busy with the move. Then it failed.
Lots of rules with them no one mentions. Not to much surface agitation. The water entering the front must not splash. That makes bubbles. The flow through the siphon must be fast enough to make bubbles go on through. Even tiny ones can accumulate over time.
The water level in the tank has to be steady. You have to clean the thing. Stuff growing in and on it changes the flow rtes enough that it will make bubbles and fail. If you have something making micro bubbles they may accumulate n the siphon and make it fail.

I never used an aqualifter pump but saw many posts where the thing had failed and never been checked.

A hole and gravity is foolproof and simple.

 

[griss]

I had one on the 75 when I moved it here. It ran flawlessly until we got busy with the move. Then it failed.
Lots of rules with them no one mentions. Not to much surface agitation. The water entering the front must not splash. That makes bubbles. The flow through the siphon must be fast enough to make bubbles go on through. Even tiny ones can accumulate over time.
The water level in the tank has to be steady. You have to clean the thing. Stuff growing in and on it changes the flow rtes enough that it will make bubbles and fail. If you have something making micro bubbles they may accumulate n the siphon and make it fail.

I never used an aqualifter pump but saw many posts where the thing had failed and never been checked.

A hole and gravity is foolproof and simple.

Agreed.

 

[kfisc]

Given the choice between a pre-drilled "reef ready" tank and an HOB overflow, I'd take the pre-drilled every time. I'd even simply buy a new tank than drill one. The question is risk (and a pain in the neck amount of work), especially if you've never really handled power tools, much less figuring out how to glue, measure pipes, so on and so on.

Tanks are big boxes of worry. A well-tuned HOB is no less worry than a first-time DIY job. But agreed, do yourself a favor and invest in a reef ready tank.

 

[wvned]

Given the choice between a pre-drilled "reef ready" tank and an HOB overflow, I'd take the pre-drilled every time. I'd even simply buy a new tank than drill one. The question is risk (and a pain in the neck amount of work), especially if you've never really handled power tools, much less figuring out how to glue, measure pipes, so on and so on.

Tanks are big boxes of worry. A well-tuned HOB is no less worry than a first-time DIY job. But agreed, do yourself a favor and invest in a reef ready tank.

You fear the unknown which can be a monster of infinite size. The reality is it's a pretty easy job that can be accomplished with a cheap set of tools available from Home Depot. Cutting PVC pipes is like using scissors. The glue comes in a can with an applicator. You take the lid off and swirl the applicator around the pipe and push them together. It grabs immediately.
The pipes can be dry fit (no glue) so you can get them correct before you glue. The skills translate to other things like adding a new sink in the fish room. That big pipe in the wall. You cut it with a bit of string.

I always enjoy getting new life skills. I just made a macramé plant hanger. That was fun too. Never done it before.
Once you learn to work with PVC it comes in pipes and boards and sheets you can have all kinds of fun making things.