PH issue ...odd please help

[marineways]

I have a tank with a auto fish feeder with pellets and granuals in it and I was away for a week and when I got back all the fish were dead exept a few clowns. What prob. hap. was one of the big fish died and alot of the food was not eaten.There was alot of food left in the tank so the amonia shot up and killed them. So I did a water change and took 75% of the food that was in the tank out and I took the surviving fish and dead fish out.
I let the tank run for a few days and the amonia and nitrite went away but the ph was like 7.4.

The problem is no matter how much buffer I put in the PH would not go up but only the alkalinity would.
I dont understand this.

Anybody have this problem before.

[bertoni]

You could do some more water changes. The decay of the food and dead animals reduced the pH. I'm not sure whether it should rise again on its own, but this article might help:

http://reefkeeping.com/issues/2004-09/rhf/index.htm

I'd do 2-3 25% water changes, myself.

[TJcop]

I was wondering: While you were away that week, did you have someone replace your evap water, or do you have an auto-topoff?
Also, are you using RO/DI water?

[DaddyJax]

Did you say you put a weeks worth of food in the day you left?

[TJcop]

No, he said he has an auto-feeder and that he was gone for a week.

[DaddyJax]

Oh okay! Sorry I am still a little new to some of the auto stuff! It just sounded like too much food got in there some how and started a tragic chain reaction. Sorry about your loss.