I'm having a mental block and reading conflicting advice - I'm nearing the end of a fish less cycle but it's been years since I did this and I can't recall:
24hrs after dosing 3ppm ammonia I'm reading Ammonia 0 Nitrite 0. 12 hours after dosing Ammonia 0 Nitrite 2ppm.
I've had the nitrite spike and drop and showing plenty of nitrates - does the filter need to be processing the Nitrites to 0 within 12 hours or 24 for the cycle to be completed? I've had these readings for a week now.
Interesting question Emma. I think I am about to make it more interesting but with the utmost respect to everyone ....... This is where I disagree with the advice given regarding the 12 hour rule for both. I was where you are for 3 weeks and the closest I got to 12 hours for both ammonia and nitrites was 18 hours. In the end I gave up and used the advice in the link below. It just seemed to make more sense to me. I put 18 juvenile fish in with no problems at all. My bacteria were more than capable with ammonia going to zero in 8 hours and nitrites within 10 hours after that. I could probably have put more than the 25% of stock I put in. On reflection i personally think it is a very big ask to get both ammonia and nitrite to zero in 12 hours. Hope I am ok to post the link below. It certainly helped me to decide on the that final question you have asked. No disrespect intended to anyone. Regards Tonto http://www.aquariumadvice.com/forums/ ... hless-cycling-148283.html
I followed the advice in the link. I added 25% in juvenile fish knowing that they would eventually grow to about 50 - 60% of my stocking level. You have to put enough fish in to maintain the bacteria you have grown but not too many to overload them and cause a spike. Which is why I picked juveniles; Everything should grow together.
The link was informative, thank you. I was intending to get just a few young platies for the tank - it's a 210l and will be heavily planted in the end. I can't see that half a dozen young platies will overload the filter even as it stands at the moment but I want to be sure. The tank seems pretty stable and I've had hardly any melting of plants.