water unstable

Question
My son set up a 75 gallon freshwater tank about 2 months ago. His water ph is very low. When he puts a ph increaser in it to raise the ph his ammonia level gets really high. He just can't get his water right. Can you help with this?

Answer
Hi Glenda,
First we should try to do some investigating on why the pH would be so low. How often does the tank get water changes done on it? If its not very often, then organics that naturally build up in the tank produce acidic compounds which lower the pH. These would otherwise be removed and kept under control by the regular water changes, but if the tank doesn't get enough frequent water changes then the pH could be subject to big flucuations.
Also if there are any driftwood or bogwood in the aquarium, these tank decorations naturally leech out tannins into the water that lowers the pH as well.

It would help out a bit if you could also test your water's ammonia, nitrite and nitrate. It would also help if you could let me know the maintenance schedule and as many details about his aquarium as you can.
This would really help. Such things as-
*How often the tank gets water changes?
*Does he gravel vacuum at every water change?
*What type and how many fish does he have?

And any other little details you might think you should add.

Feel free to get back with me on this, I will do my best to help!
Happy holidays,
Karen~