GuppyTeacher

I have a tank that is cycled and would like to set up a second tank. Can I use the water I drain off my cycled tank each week to help the 2nd tank cycle quicker? Also where do the bacteria hang out? Are they just free floating in the tank or attatched to the sides? What is the most water you could change out and not hurt your bacteria count? Lots and Lots of questons. LoL Thank you for any help.

SereneReyn

the bacteria is very minimal in the water itself, it generally likes a surface to reside on. a better idea would be to use some of the filter media (ideal) from your established tank, or even some decorations or a nylon full of gravel (not as much bacteria, but more than water). but yes, doing this you could cycle your tank faster. just make sure not to replace ALL your filter material in the old tank, or you'll send it through a cycle again. a portion is fine.

you could, theoretically change 100% of the water, and really not hurt the bacteria much at all... but people generally advise against this, because matching the parameters exactly is difficult and a non-match can be extremely hard on fish.

bio-spira is another option, but it's expensive. a bit of filter media will work great. just be sure to test the water (your info indicates you don't know the readings - i urge you to get a liquid test kit so you can keep track of it, it's key to the health of your fish!), and feed the newly establishing colony of bacteria. good luck!

Peterpiper

Hi and welcome to fishlore!
As most of the good bacteria will be " hanging out " it the filter, the old water would not help cycle the new tank.
You could take 15-20% of the filter media form the cycled tank, add it to the uncycled filter, and this would help start the cycle.
Which method are you using to cycle?

GuppyTeacher

I have a filter that hangs on the back of the tank. I have an old filter from a month ago. So I could use that one to start the second tank or are the bacteria all gone since it dried out? I was cycling fishless. I still need to get a test kit. The local fish store will test for free so I have just been taking a sample up there when I need it tested. Gives me an excuse to go out for a nice walk. Last test for my tank showed 0ppm ammonia 1-2 nitrites and 15 nitrates.

Peterpiper

Any excuse to go to the LFS. LOL
The bacteria in the old filter is long gone. Think of the bacteria as you would fish, they need water and food.

GuppyTeacher

Thank you! I could always use the filter in my current tank to seed the other tank. You are right it is a good excuse just to look around the LFS.

Shawnie

welcome to fishlore!

your tank is still going through the cycle....but its gettin there.!!

ammonia turns to nitrite then nitrites turn to nitrates..so you are in the middle and with daily water changes of at least 50%, you will see a zero ammonia, nitrite, and then nitrates will start registering...the most popular test kit is the api liquid master kit...it has all that you will need to get the results you have to achieve...goodluck

COBettaCouple

Welcome to Fishlore.

The nitrifying bacteria colonize surfaces. There are VERY small amounts in the water, but not enough to make much difference. The filter media is usually where the largest colonies are (especially the filter sponge), the substrate is usually 2nd.

The bacteria died off on your old filter, but you could run both filters in the current tank. Once the current tank is cycled, run them both for about a week and you'll have a lot of good bacteria to move to the new tank with one of the filters.