Help me please!!! Cracked overflow?
 

I was trying to drill out the grate on the overflow in my tank to get the water level down a little while still maintaining the same flow. Well, a piece of the overflow cracked out and I have had to make a piece of acrylic to cover it for now:cry:. My problem is, if the power fails now, my water level will go down to low and probably overflow the sump:embarassed:. Does anyone know of a product that I can seal in a new piece of acrylic with, that will safely(for fish, corals, inverts) cure underwater:question:? Please help!!!

I would think coral expoy would do the trick.

Can you drain the sump a little, let it run down and then air cure a new piece where you need to?

Underwater epoxy is more of a plug/filler than a glue. I would not trust it to hold two pieces of anything together for a critical application such as this.

Real epoxy applied while dry and allowed to cure overnight maybe and/or gobs of Superglue perhaps too.

An acrylic adhesive like Weldon will be the safest bet. Needs to air cure for 24 hrs though. Hold one, edit... if you can get hold of some nylon hardware, screw/nut, would that do the trick? Or even a zip tie or two in the meantime...

Thanks for the quick responses. I have tried coral epoxy for now. I have found a product called GOLD LABEL UNDERWATER SEALER but so far it seems like it is only available in the UK. Looks like amazing stuff tho. I have a week off in May, I may try to drain the tank a little and seal it with silicone then.

silicone does not stick very well to acrylic. Like mike31154 says, dry it out use weld on #4 it will wick into the crack. wait 24 hrs

Wow, I'm on a roll today. I was just reading about complete glass replacements on WWM and ran across your problem. I have never owned an acrylic tank, so I have not researched it (and really can not offer much advice) but to look here. http://www.wetwebmedia.com/acrylictkrepfaqs.htm It is a bunch of questions that have been asked about how to fix problems on acrylic tanks. If your question is not answered, there is another page of FAQ's on the same site.

Good luck