Cycling question

[Bldgengineer]

My tank has been cycling for a little over 4 weeks now. This time last week my ammonia finally disappeared with nitrites at over 5ppm and nitrates hovering around 20ppm. I dosed the tank up to 1ppm ammonia to see how fast it would process it and it went away after around 36 hours. That was Thursday so I dosed it to 1ppm again and it only took around 24 hours this time. Nitrites still unmeasurable with the kit. I tested again today and nitrites are still over 5ppm(API test kit. It turns dark purple right away) but my nitrates are gone. I tested it again just to make sure I didn't screw anything up and got the same result. I've never had this happen before. Any ideas as to what might be going on? I'm thinking either my nitrite or nitrate test kit is bad.

 

It's a 10g tank setup with all BRS reefsaver dry rock and dry sand.

[xAyanex]

I'm assuming you're using API.

 

Nitrates does some funky things in the API test kit sometimes I've found, especially when Nitrites are so high.

 

My nitrites were sky high (5.0+ super dark puple) for several days and then almost overnight they dropped to 0.25 for a few days. I got some erratic readings on my nitrates throughout the cycle but at the end they were steadily a good 80 or something like that. Just wait it out.

 

If you're worried about your test kit being inaccurate, check it with your LFS or buy a test kit from a different manufacturer.

Also, with Nitrates it is very important to vigorously (VERY vigorously) shake bottle #2 for 30 seconds before adding the drops, and then very vigorously shake the test tube for approximately one minute. Then of course wait the full 5 minutes before reading or your reading may be inaccurate. (This is for the API test kit anyway)

[Bldgengineer]

Yeah its the api kit. It's what I had on hand when I started the tank so I thought I'd use it until the cycle finished. I've never had my nitrates completely disappear like that.

[xAyanex]

Yeah its the api kit. It's what I had on hand when I started the tank so I thought I'd use it until the cycle finished. I've never had my nitrates completely disappear like that.

So your ammonia is at zero. Once your nitrites are at zero, I would say your nitrates should be high. If they're not, I would DEFINITELY check with the LFS or a different kit, because that physically wouldn't make sense.

[Bldgengineer]

So your ammonia is at zero. Once your nitrites are at zero, I would say your nitrates should be high. If they're not, I would DEFINITELY check with the LFS or a different kit, because that physically wouldn't make sense.

That's what I'm saying. My nitrates were around 20ppm this time last week and they just disappeared? It didn't make any sense to me so I wanted to make sure I wasn't missing something

[xAyanex]

That's what I'm saying. My nitrates were around 20ppm this time last week and they just disappeared? It didn't make any sense to me so I wanted to make sure I wasn't missing something

As aforementioned, nitrates may give erratic readings when nitrites are present in high quantities. Some people choose not to even test nitrate until nitrite is zero.

 

I wouldn't worry about it too much, just test for nitrate after nitrite is zero.

 

[Bldgengineer]

Gotcha. Thanks!