Water Levels

Question
Hey there. I have an emergency about my tank levels. Last night, we changed the water (added tap, and added the salt needed, correct calcium buffers etc. The Nitrate levels were pretty bad, about 80 mg/L. The Nitrite levels were at 0 ppm, ammonia at 0 ppm and the high range was 8.4 ppm. This morning, i wake up 2 of my fish are dead and my levels are out of wack, like really bad. Ammonia is still good, high range dropped to 7.4, nitrate is almost at 100, and the nitrite is at 1.0ppm. I am really nervouse, being our set up has been fine for almost a year now, and all the sudden its all wacked out. We put a new fish in yesterday,a also.. which died. And our big african clown. The other fish that are in the tank right now look like they are breathing a million miles an hour. Please HELP ME!! I need quick ideas so i can help them immediately.

Thank you,
Katie

Answer
Hey Katie

Sorry to hear about this emergency, lets see if we can fix it. I noticed you said you are using tapwater, you should be using RO (reverse osmosis) water, which has none of the phosphates and other junk that tapwater has. The phosphates in tapwater usually cause algae and cyano blooms. you might have had nitrate and nitrite in your tapwater, along with a low PH, which caused the sudden crash of your levels. i would try to get some RO water and do a large water change with it, and slowly try to buffer up the PH

any follow-up questions, feel free to ask