it isn't that big, but they absolutely love swimming under it. of course i didn't just throw random rocks into my tank. i soaked them in hot water for most of the day to get out all bad bacteria and whatnot. anyways, my cichlids love it and i am definately going to make it taller and longer. thanks everyone for the advice on what my africans would like! they are also loving the zucchini! they are all so much happier and more active!