Cracked Base - Can You Repair Them?

[simonas]

Its a 36 inch long tank that I haven;t even filled yet, bought it second hand the other week. Its got a crack along the base which must have happened this week sometiime. I've got some spare pieces of glass, if I siliconed one of those over the crack would the pressure of the water keep it sealed and is that a viable repair

 

[Colin_T]

as long as the new glass is the correct thickness you can glue a patch over the cracked base. A 36in long x 18in high tank usually has a 6mm (1/4inch) base.
Clean the old base and remove all dirt. Allow to dry and then use a glass silicon to glue the crack. Also put some silicon over the new piece of glass and then put it in place. Push down gently to settle the glass.
Run a bead of silicon around the edge of the new piece of glass. Leave it to dry for a week and away you go.
Make sure the new piece of glass covers the crack by at least a couple of inches. If the crack goes from one side to the other then cover the whole base.

 

[squeakytoy]

Another good idea when cleaning would be to do a final wipe with some kind of denatured alcohol / mineral spirits. Make sure there are no residual oils or waxes.

 

[NoRp]

i guess it all depends on how big the crack is. patching a small crack is gonna be fine but if its the whole length it may just be safer to redo the whole buttom of the tank.

 

[simonas]

its about 30 inches of a 36 inch base?

wouls normal sealant suffice appearance isn;t an issue

 

[5teady_2012]

its about 30 inches of a 36 inch base?

wouls normal sealant suffice appearance isn;t an issue

I would just buy a new piece of glass that will site perfectly in the bottom and seal the edges so its basically like a new base on top of the old one.

 

[Colin_T]

as 5teady said about just putting a new base inside the tank. Use a glasss silicon to glue it in place.

 

[simonas]

cheers guys, just got back from hols so will do that ta

 

[CFC]

Get a piece of glass cut to the exact same size of the base and silicone it to the bottom of the broken pane not inside the tank where the braces are likely to get in the way and make getting a single piece inside the tank difficult. Most hairline cracks are water tight anyway once the weight of the water starts pushing down on the polystrene sheet so you just need to reinforce the base to stop the crack spreading.