How to make a safe overflow box when drilling isn't an option.

[20 gallon nano]

Unfortanetly i bought my self a tank that was tempered glass not thinking of any further plans of a more advanced filtration then a hang on the back filter. Heres what I came up with after a few months long of thinking and trialing diferent methods of making a safe over flow box that will protect me from water to either over flow in the tank or sump and came up with this idea. I found some courter inch acrylic and siliconed a few inch tall pieces all around the top rim of the tank and made sure there was no leaks, this added about a gallon extra water volume to the tank and at the same time allowed me to drill any size hole I needed through the acrylic also making it easier to glue the overflow box straight onto the acrylic with some acrylic cement. Before I added the back piece of acrylic I cut some half inch noches for the water to drain where my overflow box would be glued on. With the overflow box not needing any sifen hose,that could stop working if the sifen would brake , I can be sure now that I won't have anything go wrong with water spilling out of my aquarium unless anything else happens.

 

[thejuggernaut]

A sketch would help, but if you siliconed acrylic to glass to make it taller, you are asking for trouble. Silicone doesn't adhere to acrylic. It will fail within a short time. You may be able to accomplish what you are talking about with glass strips, but I wouldn't be able to sleep at night worrying about acrylic.

 

[twilliard]

Use an aqualifter !
the number one failure to overflows is air buildup.
you break the siphon and return is still kicking.. flood

 

[AZDesertRat]

Why not use a HOB overflow box such as an Eshopps or Lifereef? They are pretty compact so not an eyesore and are extremely reliable. I wouldn't recommend the CPR style which requires the Aqualifter but the U tube boxes are great if you can't drill.

 

[twilliard]

I'm sorry but ALL hob overflows accumulate air
did it for MANY years

 

[20 gallon nano]

A sketch would help, but if you siliconed acrylic to glass to make it taller, you are asking for trouble. Silicone doesn't adhere to acrylic. It will fail within a short time. You may be able to accomplish what you are talking about with glass strips, but I wouldn't be able to sleep at night worrying about acrylic.

I will post some picture in a short period of time, I did this diy build about six months ago and it still strong as the first day. I forgot to mension that My the acrylic pieces were actually siliconed to a plastic rim that was on top of the tank that post tanks have. I also acrylic cemented with acrylic cement all four corners together for further support. The thought of having water go over the rim into the overflow with a sifen hose sounded pretty risky, with having the sifen break or sifen pump stop working.

 

[twilliard]

And to note..
the cpr overflows are some of the best made
noted by OP
"Siphon pump"

 

[AZDesertRat]

So did I and the U tube style are almost bulletproof when set up and adjusted correctly. The CPR continous overflow is another story though they get bad reviews all the time, mostly because they can lose siphon and depend on another piece of equipment, the Aqualifter pump.

 

[twilliard]

Lol!!
the U tube is the worst at accumulating air
and why do you ask??
a U tube has a high point

 

[AZDesertRat]

As long as the two ends stay submerged they will not lose a siphon. Been doing this 35 years and the Eshopps was the best HOB I ever owned. Nothing like an internal though!

 

[twilliard]

This is bullet proof

 

[AZDesertRat]

No, pumps fail. The CPR has a huge high spot compared to U tube types and is much more prone to failure, read the reviews.
Everyone has an opinion and you are entitled to yours just as I am mine. Thats what makes these forums work, there is no right or wrong, only different ways to accomplish the same task. I tried and didn't like the couple CPR's I had but loved the Eshopps and similar products from the past.

 

[20 gallon nano]

Everything fails at some point over time , either 2 years or 10 years unless you switch them out after couple years to new ones. My overflow box was another simple diy project involving acrylic cement and sillicone.

 

[20 gallon nano]

Here's some images to clarify what I was talking about.