Has anyone accomplished this or attempted it? I've got a 210 gallon tank coming Friday and I want to make some pretty significant rock formations in it. It's a new world cichlid tank so I want a lot of hiding places and separations set up.
Here are my thoughts so far. Obviously start by making the formation with Styrofoam and paint with concrete.
Idea 1) Put many, many coats of concrete on to thicken and strengthen the walls. Then either melt the styrofoam away or with fire. Problems with this are using fire could potentially damage the concrete. Using chemicals could potentially cause water issues(i'm worried even after many, many soaks this could be an issue).
Idea 2) Drill large, long holes all over through the bottom of the formation or top and fill them with concrete to add weight and lessen the amount of styrofoam in the structure. I take it I would have to add a lot of concrete and take a lot of styrofoam out going this route as styrofoam is extremely buoyant.
I don't really want to glue them down as this can be an issue later on when you want to change the tank up and if the glue comes loose that formation is going to shoot to the surface like a rocket.
Here are my thoughts so far. Obviously start by making the formation with Styrofoam and paint with concrete.
Idea 1) Put many, many coats of concrete on to thicken and strengthen the walls. Then either melt the styrofoam away or with fire. Problems with this are using fire could potentially damage the concrete. Using chemicals could potentially cause water issues(i'm worried even after many, many soaks this could be an issue).
Idea 2) Drill large, long holes all over through the bottom of the formation or top and fill them with concrete to add weight and lessen the amount of styrofoam in the structure. I take it I would have to add a lot of concrete and take a lot of styrofoam out going this route as styrofoam is extremely buoyant.
I don't really want to glue them down as this can be an issue later on when you want to change the tank up and if the glue comes loose that formation is going to shoot to the surface like a rocket.