Changing filters

[Wendie]

I currently have three regular kuhlis and 2 black kuhlis in a small 10 gallon tank. I am using a sponge filter since this was not meant to be a permanent home for them. I want to change the filter to an outside filter - Aqua Clear or something in the same line. I figured I would discontinue the sponge filter and switch to the new filter but leave the sponge filter sitting in the tank for a couple weeks. Should I leave it in for a longer period of time or would two weeks be enough time to establish the new filter so I don't have any cycling problems? The tank has been up and running since last July.

[Mark in Vancouver]

Run both filters for a week or so - or if you choose an Aquaclear box filter, simply submerge the AQ filter sponge in your tank, or better, in the existing filter system, so water runs over it continuously. The sponge will pick up all the cycle bacteria it needs after a week or two.

[Diana]

Depending on the exact nature of the current sponge filter, you might also fit the sponge part over the intake of the aquaclear filter.

[Mark in Vancouver]

That's true. A lot of sponges are can be adapted or used in creative ways. No matter how you do it, you should be confident that there are beneficial bacteria in the substrate as well.

I took Momfish's advice, and now I don't clean the rear wall of any of my tanks. They are all veritable reefs of different algaes and bacterial colonies. I keep the top substrate clean from mulm, and I scrub the other parts of all tanks, including plumbing. The filter materials are all rinsed in spent tank water.

I think cycling should be seen as a quick process if you have acces to one mature tank.

[sophie]

I took Momfish's advice, and now I don't clean the rear wall of any of my tanks. They are all veritable reefs of different algaes and bacterial colonies. I keep the top substrate clean from mulm, and I scrub the other parts of all tanks, including plumbing. The filter materials are all rinsed in spent tank water.

I think cycling should be seen as a quick process if you have acces to one mature tank.

I'm in full agreement on this one. One of the tanks I occasionally scrape everything off the back wall (but not at the same time as cleaning the filter). The sand is mulm & algae free, but I have a fair amount of algae gorwing on the wood and stones. I like it, one of them looks like huge delicate moss. The only one I don't like is a blueygreen slime thing that turns up occasionally, but as it's easily the easiest to get rid of (it often just disappears by itself) I'm not that bothered by it. I think it's a good nitrate sink as well. The fish all seem to enjoy rootling around in it for things to eat, as well.