I have about 250+ pounds of rock just waiting to be put in my new fish tank, and then i realized that the bottom of my aquarium might fall out under all this weight.... could it? Its a 55g and i have an inch thick peice of tile on the bottom of my fish tank to prevent weak spots. So is it fine, Can i put it in? Or am i risking it?
rock will off set the water ...stack whatever u like ..but peacock and hap doesnt like alot of rock only mbuna does...there's a guy in here "Cich of it all" << his srname....he have 95gallon bow front with 500 pound of limestone ....just make sure u put some egg-crate on the bottom
i have a fair amount of rock in my tank, i used some really large pieces of blue metal and what i did was use a layer of thick sand underneath my beach sand and i have a fairly thick sand bed which has supported the weight of the stones for quite a while.
personally i would use the egg crate and have a lot of sand or substrate underneath to help support the weight.
right now i have about 200 lbs of limestone and 100-150lbs of sand in my 90... i was told that water displaces the weight of the rocks... eggcrate is mainly for your own "self worries"... i say you are fine with what you want to do... the main thing is to just becareful your setup isn't flimsy... you don't want your rocks falling down, and possibly scratching/breaking your glass, or crushing your fish...
Just to add to the above posts:
A while back a guy who works in R&D for All-Glass Aquarium posted some pics of a tank filled to the brim with bags of lead shot, it must have weighed a gazillion pounds. The tank easily took the weight. I couldn't find his pics, I think his handle is Narwhal72.
Eggcrate doesn't seem to be necessary for static loads, but it does help if you drop a rock in your tank. One of the moderators, JoeA I believe, talked in a thread a while back about having this happen to him.
A big pile of rock is going to displace a fair amount of water...just be aware that you don't have 55 gallons of water in your tank, you have something less, when you're talking about water stability. Also, as the poster above mentioned, make sure your pile is stable, or a fishy might knock a rock off and be crushed or even worse hit the glass in the side or front and break it.