Caulk

Silicon Caulk is very helpful to make or repair your glass aquarium, but there are a few things to consider before you buy a tube of it.

Not all caulk is safe to use on aquariums. Many types of caulk have an anti-fungal agent to keep mold from growing on it. You want to be sure to get 100% pure Silicon caulk with NO antifungal agents.

We have used a product that we purchased at Home Depot. It is GE012, and made of pure Silicon caulk. However we are NOT warrantying that it is safe to use. But in our experience, it has worked well.

Be sure when using caulk to let it setup and harden before you fill the tank up. It might appear to be dry, but caulk will continue to strengthen for several days after application. I would allow a minimum of 24 hours of drying time before applying pressure to the tank or repair, depending on the load it will support.