Water change dilemma..

[cori]

I have a 75 gallon with 120 lbs of LR. I have a few mushrooms and soft corals, and a decent sized clean up crew. I have a pair of clowns and a lawnmower blenny in there as well. My tank is a few months old now.
I had a coral beauty angel that died in the tank. The problem is, with all of the LR, I couldn't find it. I took out as much of the rock, as I could, but to no avail. My nitrates have went up and here is my dilemma..
I have 15 gallons of water from my RO/DI system ready. I talked to a guy at the LFS, and he said I should change about 25% or more of my water. Now, my RO/DI unit does like 25 gpd..which means each bucket takes several hours to fill.
Should I put in the water I have ready now, or should I wait until all of the water is ready to go in? I know it is a silly question, I just don't know if it would be beneficial to put in what I have now, only to take some of it out later, only to replace it with new water.
Am I over thinking this one? lol
He also said I should put in Amquel plus every day until my levels drop back down to normal. Any thoughts on this?

 

[saltn00b]

your cleaning crew should have eaten most of it. regardless, if you feel it went up to the point of water change, then just do your 15 gals, and check the levels. if you need more, you will know at that time.

 

[mazdaman]

amquel is a great product but isnt not a fix so be sure to do some water changes 15 gallons every other day or every day would be just fine.