I am having some issues getting my 1500g tanks to cycle. It was originally cycled freshwater and switched to saltwater about 6 weeks ago using Instant Ocean (not a reef system). The rapid change killed all the bacteria, so I had to restart the cycling process.
The system is set up with a large, aerated bioreactor, an ~200g sump, and a pressured bead filter system.
The ammonia dropped to practically 0 about 4 weeks ago, and the nitrites have been between 2 and 4. I add a large "sock" (pantyhose) filled with 35% protein feed to the sumps and leave them for 48 hours. When the nitrites are approximately 3 to 4 ppm
, I remove the sock for a few days. The nitrates consistently read 30 to 40 ppm
There are no animals in the tank, the temperature is 30 to 33 C and the pH is fairly consistent around 8.4. A few weeks back, I added Fritz Turbostart to one of the systems (I have 5 of them). Four of the systems are 1500g and one of them is 500g, and have seen next to no difference in the ones dosed than the others.
I have used filter media from another cycled system to each of the bioreactors (about a week ago), and have refreshed the media once during that week.
I have ordered the API saltwater kit, we have been using strips. I would say it is a problem with the strips, but the same container that reads 0 nitrites in another system reads 3-4ppm in the tanks of concern.
They have been cycling for 6 weeks with no change in nitrites or nitrates unless we do a water exchange.
Thanks in advance.