okay so i wanted to make a rocky background that would fit my tank specifiaclly. the only thing in the tank is a fire belly newt. what kinds of cement are safe to use for that purpose or are there any like sealants that you can put over the cement so that chemicals wont leak out into the water?
Its not chemicals that you need to worry about with cement (I take it you are referring to concrete?) its the pH balance and the alkalinity of the water you need to worry about, as concrete is made of limestone that will dissolve in the water and raise the hardness and alkalinity of your tank. If you have South American fish like tetras that prefer soft, slightly acidic water, concrete landscaping will not be appreciated. African cichlids, which prefer hard, alkaline water, will have no problem with this arrangement. You can use any epoxy putty to adhere fixtures in your tank together. Most pet stores will also sell tubes of aquarium sealant that is 100% safe when dry.
