6 Months, 55 Gallon Tank Still Not Cycled

Sounds like you're on the right track with everything! I would do some research on your canister filter and try to learn about the media. It will need to be cleaned and serviced about once a month or so, so it would be a good idea to familiarize yourself with it. If you post the make and model I bet someone here has used it before and can give you a guide for maintaining it.
 
Okay, I'm a little stumped! After adding the ammonia, my toddler and I both managed to get sick at the same time, so the tank wasn't touched again until today.

When I tested it today, the ammonia was about .25, nitrites were 0, and the nitrates were 10-20ppm. The fishless cycle guides I have been reading all talk about nitrites going up and staying up for ages. I figured I just managed to miss the nitrites starting to climb by not testing before now, but should I be concerned? I was going to add a little ammonia today to get it back up to 2-4ppm then test tomorrow to see what happens, but is that a mistake?
 
Okay, I'm a little stumped! After adding the ammonia, my toddler and I both managed to get sick at the same time, so the tank wasn't touched again until today.

When I tested it today, the ammonia was about .25, nitrites were 0, and the nitrates were 10-20ppm. The fishless cycle guides I have been reading all talk about nitrites going up and staying up for ages. I figured I just managed to miss the nitrites starting to climb by not testing before now, but should I be concerned? I was going to add a little ammonia today to get it back up to 2-4ppm then test tomorrow to see what happens, but is that a mistake?
are you using test strips or a kit of droppers?
 
One variable in this cycling process is the availability of minerals used by the bacteria to grow. If there isn't enough minerals for the bacteria to keep growing the growth of bacteria needed to complete the cycle will stall. Most water sources have enough though you need to do the water changes to keep the supply up in your tank. Worst case is that the minerals get completely used up and the waste byproducts crash the ph since the buffering minerals are gone. That really stops the cycle in it's tracks. Even if you aren't keeping fish alive the tank still needs water changes to help it along.
 
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