Tank almost done cycling?

Heyo!! I have a 50 gallon tank that I’ve been cycling for the past nearly 20 days and I’m wondering if it’s almost done? I’ve been using dr Tim’s as well as stability. I’ll attach a chart of my ammonia, nitrite, and nitrate levels. (Note: I did a 50% water change on day 17) Should I do a large water change and add fish? I’m not sure what my next step should be. If you have any ideas please let me know, thank you!!

 

Heyo!! I have a 50 gallon tank that I’ve been cycling for the past nearly 20 days and I’m wondering if it’s almost done? I’ve been using dr Tim’s as well as stability. I’ll attach a chart of my ammonia, nitrite, and nitrate levels. (Note: I did a 50% water change on day 17) Should I do a large water change and add fish? I’m not sure what my next step should be. If you have any ideas please let me know, thank you!!

You'll want to wait until the nitrite is 0 and you should do a water change to keep the nitrate below 20ppm. Once ammonia is 0, nitrite is 0 and nitrate is <20, your tank is considered cycled. I would still wait maybe a week to make sure there are no other spikes and it's stable before adding fish and then I would add fish slowly. Best to not overload the cycle by tossing in too many fish at once.

 

You'll want to wait until the nitrite is 0 and you should do a water change to keep the nitrate below 20ppm. Once ammonia is 0, nitrite is 0 and nitrate is <20, your tank is considered cycled. I would still wait maybe a week to make sure there are no other spikes and it's stable before adding fish and then I would add fish slowly. Best to not overload the cycle by tossing in too many fish at once.

Should I add any more ammonia at some point?

 

You should actually be fine without doing a water change yet (I misread something, so disregard earlier when I said to do that). Basically, keep adding ammonia (If you're using Tims, do about 5ml to get ammonia up to 2-3ppm) until you get 0 ammonia and nitrite after 24 hours. You want to see only nitrates. Then, once they're both 0, do large water changes until the nitrates are below 20ppm. Once they're below 20ppm, you can add fish.

 

Your cycle seems to be moving along.

Because nitrates are being produced, I’d say you’re getting close. Contrary to the post above, nitrates don’t have to be less than 20 for a tank to be considered cycled. A tank is typically considered fully cycled when you have 0 ammonia, 0 nitrites and some level (not necessarily less than 20) of nitrates.

I‘d suggest you also take a pH reading of your tank. So long as it’s above 7 (I suspect it is), there’s no need for a water change and I’d redose ammonia to 2 or 3 ppm. Once the tank is able to process 2 or 3 ppm of ammonia in 24 hours and you’re showing 0 ammonia and nitrites and some level of nitrates, you’re cycled!

Once cycled, I’d suggest a large water change before adding fish.

 

Your cycle seems to be moving along.

Because nitrates are being produced, I’d say you’re getting close. Contrary to the post above, nitrates don’t have to be less than 20 for a tank to be considered cycled. A tank is typically considered fully cycled when you have 0 ammonia, 0 nitrites and some level (not necessarily less than 20) of nitrates.

I‘d suggest you also take a pH reading of your tank. So long as it’s above 7 (I suspect it is), there’s no need for a water change and I’d redose ammonia to 2 or 3 ppm. Once the tank is able to process 2 or 3 ppm of ammonia in 24 hours and you’re showing 0 ammonia and nitrites and some level of nitrates, you’re cycled!

Once cycled, I’d suggest a large water change before adding fish.

That was poor wording on my part, sorry! It would be cycled once ammonia and nitrite are 0 and there's any nitrates. I just know nitrates under 20ppm are typically what people go for when adding fish/keeping fish.

 

One thing I did want to point out. If this tank will process 2 or 3ppm ammonia through to nitrates within 24 hours it will be ready to fully stock it. There is no need to add just a few fish at a time. There should already be enough bacteria to handle the bio-load of a fully stocked tank (within reason of course)