This is what worked for me....U2 CAN CYCLE A NEW TANK IN LESS THAN 2 WEEKS
The best thing going for you is you have a current set up in place already. I did too, so One thing that worked out GREAT for me was that I used much of the same decor and water out of my old 135 tank for my new 220 gallon. If you have a new filter, run it
AND the old filters as well for a while to circulate the beneficial bacteria. I did not want to use the old gravel because I wanted sand, but I used a container filled with the old gravel and placed it in the aquarium with the new water. I would stir the gravel once a day and release some of the bacteria that way. I did this for about a week. WHATEVER YOU DO NOT GET CLEAN THE OLD FILTER, LET IT GET THAT NEW WATER DIRTY. IT WILL NOT BE DIRTY LONG.
(I did the next process in addition to the above process from a friends cycled tank)
IF YOU DO NOT HAVE THE OLD TANK SET UP ANYMORE...TRY THIS.
If you know someone with a large tank, ask them if you can "borrow" a filter or have their old media. Sometimes a LFS (reputable ones) will give you old media as well, they have plenty of it. Dirty, nasty old media is a GREAT way to get a new tank going quicker than any chemicals you can buy, especially the expensive ones that are availablebecause it is full of good bacteria to break down ammonia and food particles. I took the old foam media in a large plastic bag and then literally poored the dirty water directly into my tank. I then squeezed the foam and dispersed it throughout the aquarium. It will cloud the water real bad, but after 12 hours it will begin to clear up nicely. 24-30 hours later that tank will be VERY clear. With a week, that tank WILL BE CYCLED. Conduct a 25% water change weekly. Test water perameters daily.
I purchased my 220 gallon around January 3, 2007.....and it is already cycled......

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