Cycling a Tank

[DanL]

Once your tank starts to cycle does the tank stay cycling even after taking all fish out?

in other words... If a tank has been cycling for a couple of months and all fish are removed, and for a couple of months no fish are in the tank but filter is left running can any fish be added back into the tank with having to start the cycling over again?

[VoodooChild]

Yes and no. Once the tank has started cycling, it goes until it's done. If the fish are going to be taken out anyways, it's better to just use some store bought jumbo shrimp to get things going (better to do this anyways). However, you said a couple of months. Cycling generally only takes a month, sometimes as little as 2 weeks, and sometimes as long as 6 weeks. A false cycle can occur when bacterial populations never truly build up to what they need to be to get rid of ammonia, but I wouldn't worry about that. So in short: yes, it'll continue and it'll only take a month:)

[DanL]

thanx...

thats what I figured but I just wasnt sure...


I am going to be setting up tw0 15 gallon tanks. On is going to be for breeding and the other for the fry.

But I do have a few fish that I can switch around to keep the tanks cycling when no breeding is going on...

Why do you recommend jumbo shrimp?

[anonapersona]

You can also keep the bacteria alive by either feeding a bit of fish food to the empty tank, or by adding a bit of ammonia to the empty tank.

Or you could move the filters to the same tank with fish and when you need to get the other tank going, just move one filter over.

I have cannisters on the two larger tanks, but one holds a spare HOB filter that is running. should I ever need to sert up a Q tank (now dry) I can take that running HOB filter to the Q tank, and start up a spare HOB in it's place. (I got lots of small HOB whispers at garage sales last summer)

I figure the tank with the cannister won't really miss the HOB much, and the Q tank will be so lightly stocked with fresh water that the load won't be much.