black rubber around tanks

[penny5h]

Forgive me for I am very new at this, however my whole life I have always wondered what the black rubber was around the big tanks at the public aquariums. I'm sure the answer is here somewhere amongst all these posts, but I can't seem to find it. Is it used to hold the acrylic to the tanks or hold the tanks to the exhibit? Sorry again for such a juvenile question, just wanted to know

Penny

[Viktor Jarikov]

I'd like to know (much more) as well. It's purpose is to provide a leak-free connection between the acrylic panes and (usually) the concrete walls of an aquatic enclosure.

My limited and surely "correctable" understanding is that the seal is made of either silicone or a rubbery polymer they call "butyl". I have been asking around what it is but no one has told me this yet and no description have I found on the web.

Neither material has a strong enough adherance to concrete or acrylic to hold the window glued to the wall without any support - the support is the tremendous water pressure that pushes on the window and squeezes the seal in between the window and the wall. This is the reason in many DIY tanks (made like that) people prop the window say with a piece of wood to prevent it from falling backwards when they empty their tanks.

In Public Aquaria tanks I think they often would use a frame, e.g., out of stainless steel, attached and sealed to the concrete walls. The frame holds the sealed window not allowing it to ever fall back. This, however, creates two seals. There are other simple ways to secure the window.

[penny5h]

Thanks for the info. I've been searching the Internet but because I don't know the technical terms I haven't been able to find it

Thanks again