Agreed, you must get to the root of the water issue. You should contact your water supplier and get a current analysis before attempting to medacate. Definatly test your tape water to get a base line. If your ammonia is spiking after a water change you should increase your bio-capacity too.
I have tested the tap water and the nitrates are really high, i think the ammonia spiked because i changed like 70 to 80 percent water and caused a mini cycle. I added 2 water fall type filters with bio wheels to kick up the bio capacity. The tank has never spiked like this before when i do normal water changes of 20 to 30 percent. I have this 125 gallon tank and an 80,75, two 55,a 40 and an 18 gallon bio cube. All of my tanks are running and i have no water problems anywhere else and this morning everything is back to normal in the gar tank as far as ammonia its back to 0.
so i think it was a mini cycle.
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