SINKING PLEXI glass

so my fiancee and myself built a fresh water water fall in a 20gal tall glass tank. we woke up this morning to notice that the water fall is sinking! we used plexi glass to form the water fall ledge and used hotglue and silicone sealant to adhere the plexi glass to the sides of the tank. any idea of what else to use to make it not sink?

 

do you have any pics so we can better tell what happend?

 

not at this time ill try to get some pictures tonight its just strange how the aquarium silicone isnt holding it up! we also have two pillars supporting the front of the water fall ill try to draw it up

 

did you hot glue first and was it 100% silicone how long did you wait for it to cure you should use 100% silicone sealant you can get it at home depot it will be with the plexi glass/glass section of the store its like 5 bucks and it is in a red tube and on the front of the tube it says what it is intended for plastics, lexan, plastic to glass i use it to glue up my sumps/refs worked great for me, when i use hot glue it is just to keep the pieces of plexi in place while i silicone them good luck to you

 

Silicone & hot glue are not for plexiglass, unless they've come out with some new ones. Silicone works great for glass & ceramics.

 

Silicone does not stick well to plexi in general. Maybe if you had let it cure longer (24 hrs minimum). As for hot glue... My gut tell me that this is not a good idea - not sure if it is water proof.

I would drain the tank, let it dry. Remove the silicone in place with a razor blade and try again. Let it cure 24+ hrs before adding water.

Z

 

ya we let it cure for about 48 hrs the hot glue was used to hold the plexi in place then a healthy bead of aquarium sealant on all 3 sides of it

 

aquarium silicone has a 7 day curing wait the kind i recommenced has 24 hours

and it is made for plexi to glass sealing just clean it with rubbing alcohol first to in sure a clean surface

 

Acrylic/plexiglass does NOT bond to silicone, no matter how clean the surfaces are. If your tank is glass, you will have to get some serious stuff from a contractor store, I forgot what it is called. Otherwise, anything you buy off the shelf will not work. You will need to get a sheet of glass and bond it with silicone and ditch the acrylic.

 

what tiger mike said +1 it wil never work for long