About to start a new small tank. Will running the new filter in the established aquarium and eventually, placing 50% aged water from the established tank into the new speed up the cycling process?

Thanks.

Using aged water won't do anything, unfortunately, as the bacteria you're after live mostly in the filter/media. Are you going to be running two tanks at once, or are you putting the contents of the old tank into the new one?.

I intend to run 2 tanks. Will running the filter intended for the new tank in the established one have a more beneficial effect as opposed to running it straight in new water and aquarium??

The best method I've used is to use squeezings from your existing (mature) filter and add them to the new tank. You can just leave the new filter running in the old tank for awhile but I've heard that can take 2 weeks-a month before the bacteria in it has built up enough.

.... maybe I will go buy some bacteria from the LFS. No experience of that stuff though. Is it OK to plant the aquarium prior to it being fully cycled?

Thanks.

If you can run the new filter on the established tank for 3 to 4 weeks, you will definitey have bacteria to start the new tank. If you don't want to cut extra holes in the cover to install the new filter, just add the media for the new filter to the filters you already have on the old tank (if you have room). Run them that way for 3 or 4 weeks and then all you have to do is move the media to the new filters.

I doubt if you will be able to get any edia from your LFS. Most run on a filtration system that doesn't lend itself to removing media. As far as plants are concerned, if you are doing a fishless cycle, the plants can use up some of the ammonia rather than it beng processed by the filter. Some say this slows the process butI've cycled with plants before and not had any problems. They will get pretty grungy though with all the brown algae that comes with new tanks and cycling. Most people say a heavily planted tank can actually be stocked slowly from the start as the plants will help take care of the ammonia but I'm still a little leary of trying that.

Thanks for that! My existing tank is running a Fluval 304 cannister and I intend to buy an Eheim Aquaball for the new tank. I suppose I could just take the sponge medium out of the Aquaball and stick it into the Fluval for a couple of weeks to get it going

Maybe I will leave plants until later.

You should be able to put all your media into the Fluval. I am running the same ones on my 75 gallon and there is plenty of room for media in the baskets. After they have run for a while, just take them back out and put in the new filters. Just keep an eye on the old tank for a few days after. Since you are rimoving some of the bacteria, you could possibly (not likely though) see a mini cycle in the old tank as the bacteria catch back up. That should usually happen in about 24 hours though.

Thanks!!