What silicone to use??

[Woja222]

Ok, I know that everyone is going to say don't do it but I will have bracing to support it so no worries. I need to know what the best silicone is to bond an acrylic overflow box to the back of my glass tank?? I plan to scuff the acrylic to give it something good to grab onto. So, what silicone would best suit this application? It's for my external coast to coast overflow.

[Peter T]

Hehe yeah I pretty much would suggest you don't do it. I made an acrylic custom aquarium about a year and a half ago out of silicone (before I did any research) and it lasted a total of 10 minutes with water. I had to scrap it and remake the tank with brand new supplies using Weld-On #4 to do it correctly. Granted the pressure on an aquarium is way greater than an overflow box.

But, for baffling for my old sump, I used this:
http://www.loctiteproducts.com/p/cntct_silicone/overview/Loctite-Clear-Silicone-Waterproof-Sealant.htm

I am pretty sure it will work for your project. Hopefully you get good results and good luck :)

[dlp211]

Don't do it. Braced or not, this is just going to end in disaster. If I were you, I would simply go to your local glass shop and get the pieces needed to make your own box.

Is this more expensive then your current situation, in the short run, yes, in the long wrong NO. The silicone is going to eventually peel from the acrylic and you are going to get a leak or perhaps worst, the box will just fall off.

Then while you wait for your glass to be cut, go order some momentive R103/8 and use that.

[jimmyj7090]

I have installed many acrylic overflow boxes in glass tanks. Silicone doesn't ahere to acrylic with the strength that it will to glass, but it adheres plenty well for an overflow box.

Ever seen a off the shelf "reef ready" tank? How do you think they stick their overflowboxes in there?

Do use RTV100 series or equivilent.

[Woja222]

Thank you! That was the kind of response I was looking for. Where might I find something like that and who makes a good one?

I have installed many acrylic overflow boxes in glass tanks. Silicone doesn't ahere to acrylic with the strength that it will to glass, but it adheres plenty well for an overflow box.

Ever seen a off the shelf "reef ready" tank? How do you think they stick their overflowboxes in there?

Do use RTV100 series or equivilent.

[j tavares]

GE silicone 1 clear works great for mefrom lowes

[jimmyj7090]

Thank you! That was the kind of response I was looking for. Where might I find something like that and who makes a good one?

You can order it from Grainger.