40gal FBT Vivarium..

[jetgirl_87]

Alrighty...

I have a 40 gallon (36x18x15inches). I'm going with tropical meets siberian streamside viv so there will be a waterfall and stream as well as lush plants.

In order to do this I need to foam the back of the tank, is it necessary to silicone the entire back side of the tank first? If so how thick does the silicone need to be?

More questions.. and eventually pictures to come!

-Jetgirl

[Jason]

Nope. GS will stick to the glass, just lay it down on it back and spray it slowly and about 3/4" away from the sides and bottom as the expansion may crack your glass, after that has cured you can use a tiny amout of pressure on the trigger to apply a small bead of GS to the gaps and it will fill in. But if you go with silicone following the " better safe then sorry" method then it only has to be about 1/16" thick.. just eyeball it

[jetgirl_87]

So adding silicone is a way of preventing stress on the glass? How much should I apply to the glass? I am not taking any risks.

[Jason]

No no no the silicone wont stop the outward pressure of the GS its just used by some people to help it stick better. all depends on the humidity where you live i suppose, i had no problem with it sticking to every damn thing it touched lol, but some peeps have troubble with plain glass

[Waterkeeper]

You don't need to put down the silicone first, just put the GS right on the glass.

if there is a part of the GS that will be visible touching the front piece of glass, then you can put the silicone first just to make it look better.

[jetgirl_87]

I live in a relatively dry area so I shouldn't have a problem with GS sticking to the glass initially. What about when it is finished, should I be worried about humidity wrecking the background after?

[Rainfrog]

The idea of silicone on the glass serves 2 purposes.

1. GS looks like crap through the back of the tank. So it is great for looks.

2. There are reports of the GS detaching from the glass after afew years. the silicone will adhere to the glass better than the GS and the GS will adhere to the silicone better than to the glass so it is the better safe than sorry, looks better method.

it does not need to be thick at all. I put the silicone on and spread it across the glass with a putty knife. I make thick enough to just not be see through (I use the black, white or brown could be used to preference).

[jetgirl_87]

Thank you Rainfrog that was exactly the type of answer I was looking for... very helpful.