Ammonia levels in tank are getting high

[academyy_xx]

My ammonia levels are at 1.0 right now and they were at a normal level last week. I just did a 30% water change two days ago and I just checked a few mins ago and the levels are still between 1.0 and 2.0. How can I solve this?

 

[librarygirl]

Just water changes, really. Test your tap water, make sure the ammonia isn't coming from there. If not, do a couple of 50% water changes with dechlorinator to try to get ammonia down as low as you can. To try to figure out what happened, I have some questions:

--how new is the tank? Is it cycled?
--what are the usual levels of ammonia, nitrite and nitrate before the spike?
--what's your PH and has it fallen from what it usually is?
--what test kit are you using?
--have you added any fish or removed anything from the tank (changed filters, etc)?
--what size tank and what fish do you have now?

 

[academyy_xx]

Its a 20 gallon tank with two red tail sharks, one tiger barb, one black banded leporinus. I changed the filter cartridge when I did the 30% water change 3 days ago. I've had the tank for a month and at first the levels were high but after a few water changes they stayed at 0.25. Then last week it was at 2.0 and thats when I did the 30% water change, but I checked it today and it was still between 1.0 and 2.0

 

[vao71]

Never ever EVER change your filter cartridge!!! That is most certainly the cause of the ammonia spike, if you must clean the cartridge just rinse it in tank water being taken out of the tank. The majority of your beneficial bacteria is on the cartridge. Just keep up with water changes and learn from mistakes

 

[academyy_xx]

Oh that's the problem then!! It tells me to change it every 3-4 weeks on the box so that's why i did it. How can I fix this now?