Check the calculator I posted in the Calculator stickie.There may not be a good answer to this question post setup of a tank but how does one figure out displacement?
I've been trying to figure out my total water volume as I've been gearing up to dose BRS 2-part. I have a 90 gallon with a 30 gal sump and lots of rock but I have no idea how to figure out its displacement.
I've heard people mention weight of rock but what would that have to do with it? If I place a sealed "orb" or something that weighs next to nothing in a tank along side a rock of equal mass they're displacing equally aren't they?