These rock look-a-likes are a wonderful alternative to real rocks for they can be stacked without worrying whether they will fall and injure a fish or hitting the glass. They are very nice looking. They did come apart sometimes and had to be put back in place. Large fish can dislodge them.

Pros: Not heavy

Cons: Sometimes came apart

This product is good for frogs also. They like to climb on it.

Pros: durable

Cons: none

these are cool. my koi likes to knock things over and he hasnt done a good job at distroying these. they also look really nice in my tank and i dont have to worry about my acrylic getting scratched

Pros: not heavy

Cons: my koi likes to mess with them

I have this in one of the tanks and the Dojo's love hiding out under it. The best part of the look,is that over time,the colors have darkened from a slight algae buildup and the rocks now look like they've been there forever. Looks very cool now.

Pros: You can add on to it-safer than real stone

Cons: none