Sealant that can be applied underwater

[dmolavi]

I need to seal a joint between one of my sump baffles and the sump. I'd rather not drain the thing and run without it for 24 hrs if it can be avoided. Are there any sealants that can be applied underwater that will cure properly? Will reef-safe epoxy bond to glass and acrylic?

 

[tedisabum]

This stuff sets underwater and is approved for items containing drinking water.

JB Weld 8277 2 oz Waterweld Underwater Epoxy Putty | eBay