low PH in 55 gal fresh

Question
i have a 55 with a med size oscar,2 small convicts,2 turquoise severums,2 firemouths, a red devil and a pleco, my PH is running about 6.0!! I was doing about 25% water change weekly, PH WAS ideal dfor a while (tank has been set up about 6 weeks)i have tried PH up after trying the PH tablets and it is still too acidic!! Talked to a fish store person and they suggest a 15% changw every other week, they said i was changing too frequently? I do a gravel vacuum once a month (as best i can due to a lot of structure set up in the tank on the bottom) any suggestions??? thanks!!

Answer
Hi Chuck;

The gravel should be vacuumed every week in tanks with bigger types of fish such as yours. I'm so sorry you have been misled by people who should know better. What I am about to tell you will sound harsh, but true; The fish store is absolutely WRONG! Big fish like your cichlids need WEEKLY 25% changes and weekly vacuumings. It's frustrating and sad to see that they are giving out such dangerous information. Good grief. Don't add any more of the pH chemicals. It causes a rollercoaster effect of pH fluctuations that are much more dangerous than the fish living in 6.0 pH. Your fish like that pH and softer water. It's actually an "OK" level as long as it doesn't drop into the 5.9 range or lower. Just make more water changes more often and vacuum to eliminate waste so it doesn't get worse. Do your best to vacuum under the structures. It is absolutely necessary to get waste out from under them weekly. Junk just naturally settles there and it rots, creating dangerous gasses and growth of harmful organisms...and possibly death.

You have another serious issue coming in the future too. It's actually too crowded in there with big messy fish for it to ever really be biologically stable. Those fish are all going to get big and a 55 gallon is only barely big enough for the two oscars all by themselves. It will all just get worse as the fish grow I'm afraid. The more waste that goes into the system, the more minerals are getting "used up" so it can't maintain it's pH.

The fishes you currently have are very aggressive and territorial too. They won't all survive as they get bigger and begin to mature. Here are the future sizes and profile pages of all your guys;

Oscars 12" to 15"
http://www.fishprofiles.com/files/profiles/475.htm
Plecostomus 6" to 12" (depending on type) http://www.fishprofiles.com/profiles/list.aspx?term=pleco
Convicts 5" to 7" http://www.fishprofiles.com/files/profiles/528.htm
Severums 9" http://www.fishprofiles.com/files/profiles/463.htm
Firemouth 6" to 8" http://www.fishprofiles.com/files/profiles/512.htm
Red Devil 10" http://www.fishprofiles.com/files/profiles/374.htm

Read about each type as much as you can so you know what size tank to get for them. Looking at what you have, in order for them all to be healthy and reach their adult size without killing each other you will need at least a 200 gallon tank. No kidding....200 gallons at least. If the fish store people told you that these guys can all live together in that 55 gallon, please find another store. They have given you a lot of very bad advice and don't deserve your business. I'm so sorry this has happened to you and your fish........

At Your Service;
Chris Robbins