Swapping filters while cycling

[Etunes]

Ok, so when ever i start a new tank i have awlways just cycled it the old fashioned way with throwing food in it everyday then just doing a PWC once it is cycled then i start adding fish. But i have seen many people just throw there filter on a old established tank and let bacteria grow in it from that old tank and put it on the new tank. So

My first question is how long would you keep it on the tank before putting fish in? Do you wait on putting fish in or can you put fish in right away?

My second question is the reason why i am asking this is because i called my LFS and asked how often they see a fire eel in there shop and if they knew i could get 1 locally. Well it turned out that the guy that owned the shop has only ever seen 1 pass through any store in my area the past year (it was his store). So i thought "well i am not getting my fire eel" but the guy suddenly stopped me and said "we got a mistake in our order of fish and accedintly got 2 8 inch fire eels in. So i am super excited right now. So on to my second question, can i just throw my filter and my sand from my 20g that has 1 gold gouromi, 1 festivum, 1 bichir, and 1 pleco and put it on my new 75g i am getting and transfer all my fish over and maybe in a week or so get the fire eels? I might be getting rid of the pleco because i don't want a common pleco.

 

[mgamer20o0]

best if you moved over the substrate also but it isnt a must. you will prob go though a mini cycle.

 

[eah]

Good question about how long the new filter media would need to load up. My guess is a week or two, but I don't have any evidence to back that up except that when I set up a QT tank I'll put my QT filter in my main tank for a week or two ahead of time and haven't had any trouble. Of course, I'm usually only QT'ing a small number of fish in a relatively large tank.

Do you have anything from your tank such as driftwood or plants that you could move into the new tank? Those could also be a source of good bacteria.

 

[mfdrookie516]

i am not sure how long you would need to run the filter, but i would say a week or two at least. What i have done since i got my first 2 tanks cycled was either swap out cartridges or steal filters entirely... When i set up my 150, i took all three filters i have on it from other tanks, needless to say i added fish 3 days later with no ammonia and 15ppm nitrates... I think another thing that helped was that i used some rocks from other tanks as well. Id say if you were in a real bind and just "had" to have the fire eel, you could steal enough stuff from existing tanks to get one set up in a few days

 

[jsoong]

My first question is how long would you keep it on the tank before putting fish in? Do you wait on putting fish in or can you put fish in right away?

I don't think you should wait a week or 2 as suggested above to transfer the fish, unless you are willing to feed the bacteria. The bacteria in your filters are live, they will start to die if there isn't an ammonia source - ie put into a tank without fish. Whenever I do QT, the filter stays in the main tank until the fish is in my QT tank, then I move the filter over.

If you want to move the filter before hand, you should be adding ammonia just like a fishless cycle. This may be advantageous if you are moving just part of a filter (so your other tank won't get a mini-cycle), or if there is not much bioload in the other tank. By moving the filter ahead of time & adding ammonia, you can build up the bacteria colony in the filter to handle a higher bioload.

 

[Etunes]

Well if i did this i would transfer EVERYTHING. Substrate, plants, a couple of rocks, and a filter. So do you guys think is hould do it right away? or wait a week? Because i would transfer ALL the fish weither with it. So should i wait? or do it right away? And after i transfer all the fish would you think a week would be good enough to add my 2 fire eels?

 

[Etunes]

bump?

 

[spoonman]

I would transfer the filter and whatever else you want in the new tank and go get the eel and put it in. I do it all the time. I always keep an extra filter going on my active tanks. When I need to set up a new tank or a qt I just fill the new tank with dechlored water, and whatever else I want in the tank and add the fish, no waiting necessary. If you move the stuff and dont put an ammonia source in, the bacteria will die, defeating the purpose.

 

[Etunes]

Cool thanks guys. So the tank is being delivered to me on Monday. So i am going to see if i can make it to the pet store tommorrow or some time this next week to get more sand/plants for my fish. Thanks you guys. So when i get the tank i will just transfer the fish to the new tank and then in about a week get my 2 big 8" fire eels.

 

[spoonman]

Sounds like a plan. Congrats on finding the eels!!!