rock/cave formation attempt

[Homer8]

does anyone know if blue stone is safe in the aquarium?

 

[huma-huma]

if you can't est. if a rock type is tank safe...next time you do a pwc, just use the tank water you're pulling out, fill a five gallon bucket and place a decent sized rock in there...all you have to do is simply test the bucket water every day/2 days...if your ph or anything spikes thru the roof...you'll know its not tank safe.

oh and ps. did a pwc last night...fish are doing great! I think they are more comfortable with this new design..