water changes

[redeye]

my tank 40 gal bilt in overflo it is at 80 degree and the water evaporates quick. im puting in a gal 1 1/2 weeks .which leaves no room for water changes. i have 1 in of crushed coral and 1 inch of sand .i have a fealing i have to much of something. my water condition all reads good levels. i have 30 lbs live rock.as i put in purple up its not doing anything at all color wise. im wondering why my rock white dusty look. for now im running a berlin skimmer but soon to change

 

[tike]

Not sure what your asking here. A water Change involves physically removing a certain volume of water and replacing it with the same volume of new water......so i don't understand why you don't have room for water changes.

Also the berlin skimmer sucks! Replace as soon as you can.

 

[Kasey]

Live rock color changing varies, as with the time it takes.

Your evaporation is normal and you should be topping off with unsalted water. You still need to do your water changes with newly salted water. You do both, not one or the other....

The dusty white on your rocks could be detritus or sand. If you blow on it with a water filled turkey baster or syringe, does it fly off into the water?

Photos of course would help.