Molly Fry In Uncycled Tank

[kojote]

i recently (as in, just now) bought a 5 gallon tank for the purpose of it being a nursery, or quarantine tank, or potentially down the line a beta tank. i set it up, put gravel and plastic plants in and added the necessary amount of water conditioner as well as Top Fin Bacteria Supplement, which is supposed to add bacteria to new tanks. what i was wondering is, would it be possible to move my molly fry (there are about 5) into this tank without harming them, even though it's uncycled and brand new? if not, how soon can i do that? i poured some of my established tank's water into the new tank, and also lifted the filter cartridge out and let some of the gross water drip into the new tank, as i read on the cycling guide on this forum that adding that to a new tank would help speed things along. any advice?

 

[Akasha72]

Hi, how old are the fry?
 
Basicly new born fry have a very small bio-load and so produce only very small amounts of toxic waste (ammonia/nitrite) the smaller the fry the smaller the bio-load and so it is possible to add them to an uncycled tank and get away with it .... but ... it does depend on the fry size. I did once add newly hatched cory fry to an uncycled tank with a brand new sponge filter and successfully raised them without any ammonia or nitrite spikes. That said - molly fry are much bigger than cory fry.
 
I would say to play it safe. If you have an established tank with an established filter is it possible to steal a little media from that filter - you will only need a very small amount for 5 baby fish and additional bacteria will grow with the fry.

 

[kojote]

they're about 3 days old! not very big at all, maybe 1 and 1/2 cm long at the most? as i said my tank is brand new, it hasn't been set up for more than an hour at the very most, would that still be all right to house the babies in?

 

[fluttermoth]

It's not the age of the tank that's important; it's the amount of bacteria in the filter.

You might get enough bacteria from squeezing your current filter media into the new tank, but you would need to test for ammonia and nitrite daily.

An piece of actual media would be much better, although you would still want to test every day to be on the safe side.

 

[kojote]

good to know, thank you! i took the current filter cartridge out of the established tank, rubbed some of the gunk that had collected on the back of it onto the new tank's cartridge and put them both back, hopefully that'll help kickstart the cycling process. i'll wait awhile, a few hours to a day or so and then add the babies, maybe replace some of the water in the new tank with water in the old one to help a little more. thanks very much for the advice! 

 

[eaglesaquarium]

The water won't really matter much.

 

[Akasha72]

agreeing with fluttermoth and eagles. The bacteria is in the filter mostly - you get some in established substrate aswell but the best of it is in the filter. Provided you don't over feed these little one's 5 baby fish will produce only small amounts. If you have transferred some bacteria from your established tank to the new filter then you should be good to go ... but as Fluttermoth has said do still test the water daily (even twice a day) for ammonia and nitrite as baby fish are far more sensitive to spikes than the adults. Spikes will make adult fish ill but it'll kill a baby very quickly.
 
For future reference - if your planning a breeding programme and plan to set up this tank on a occasional basis when you have fry then consider keeping the sponges for the fry tank in the established filter of your main tank. That way you can steal the media back out as and when you need it