water

[ScubaDiver93]

how much water do i need if i have 1 inch of sand, 150lbs. of live rock, a 180 gallon tank and around 45 gallons of a sump and around 5 gallons in an auo top off.

 

[CalvinC4S]

This is like guessing how many golf tee's are in the bucket.

What type of rock?

My guess is about 179 gallons

 

[jdieck]

Try this calculator, it will aproximate the water volume as well as the weight of the main tank.

http://home.comcast.net/~jdieck1/volcalc.html