Fishless Cycle Nearly Done :)

[Wills]

Hi there been fishless cycling a 20g filter in a 10g tank for about a month now and the filter is doing 4ppm through to 0 ammonia and 0 nitrite in about 18 hours though ammonia is going through much faster about 8-9 hours. But hopefully I get to pick up my 30g today so going to be swapping the pads over to the new bigger filter and get new pads for the 20g filter which will stay in the 30g as well. Hoping this change over will only put a few weeks onto the cycle maybe 2 if Im lucky. What do you guys think?

Also once the cycle in the new tank is going through in 12 hours how soon can I add fish? I know about the big water change before hand but how many fish do I add after the fishless cycle? Should I add stock as normal or am I ok to add say a large school straight away?

 

[m00se]

I'm not sure I fully understand what you're planning to do with the filters. You're getting a new 30g tank? Or a new "30g filter"? When you say that, do you mean a filter suitable for a 30g tank? There's no such thing as a '20g filter' or a '30g filter', filters are rated on how many litres per minute or gallons per minute they put through. If you mean you're getting a new filter, if you put the new filter in the tank with the existing, part-cycled media in it, you're at the same place in your cycle. The only way you'd set your cycle back would be if you removed some of your existing media completely from your tank.

As to your second question, when your cycle is done, i.e. as you say, processing 5ppm ammonia to 0 ammonia and 0 nitrite in 12 hours, just do a big waterchange, and then you can stock your tank to its full capacity straight away.

 

[OldMan47]

You are going to see a significant shortening of the cycle time in the new 30 Wills. The 4 ppm in a 10 is much less than it would be in a 30, 3 times less total ammonia, but it is enough to have given your media a good starting colony of bacteria. If you move on to fishless cycle the 30, it should progress very quickly with the jump start you are giving it.