What Would You Do?

[emilythestrange]

When my fishless cycle is complete and drops the ammonia in a short space of time.
I am looking to moving my currrent 3 guppies and 5 tetras to my 100 litre tank...

Should i do this after the cycle is complete?
im worried about losing my healthy fish in the 27 litre tank.
i was going to introduce new fish after my old ones have gone in (about 1 week later) in stages.
But im now confused about whats best as i havent ever done a tank transfer and my little tank is stable and the fish are doing well.

aaaaah dont know what to do!!!

 

[Honeythorn]

ALWAYS complete the cycle before adding any fish. Otherwise you will expose them to high levels of nitrites and ammonia.

When your cycle is complete and your Ammonia and Nitrite are reading 0, and your nitrates are around 15-20 ( add a lot of live plants too to help use up excess nitrate ) do a water change and add all of the water from your small tank along with any fresh dechlorinated water, to help the newly introduced fish adjust to the water chemistry in the new tank. You can also take all the used media from your small tank's filter, and add it to the newly cycled filter to boost the bacterial colony.

Add your old fish, wait a week as you said and then slowly add 1-2 fish per week after that until you are stocked.

 

[emilythestrange]

ALWAYS complete the cycle before adding any fish. Otherwise you will expose them to high levels of nitrites and ammonia.

When your cycle is complete and your Ammonia and Nitrite are reading 0, and your nitrates are around 15-20 ( add a lot of live plants too to help use up excess nitrate ) do a water change and add all of the water from your small tank along with any fresh dechlorinated water, to help the newly introduced fish adjust to the water chemistry in the new tank. You can also take all the used media from your small tank's filter, and add it to the newly cycled filter to boost the bacterial colony.

Add your old fish, wait a week as you said and then slowly add 1-2 fish per week after that until you are stocked.

yes i will definately complete the cycle, im worried cause i had problems with my other one starting up.. but if i dont over stock i dont see why there would be a problem.
afraid i cant use filter media because the little tank will be a home for a betta when my big tank is complete.
i havent got live plants... used alot of silk plants for coverage.

 

[Truck]

Add your old fish, wait a week as you said and then slowly add 1-2 fish per week after that until you are stocked.

isnt that the point in fishless cycle? so you can add the fish instantly?

if youve spent all that time cycling and then your putting 2 fish in a week the bacteria in the filters will die of and a fish in cycle will start.
if your doing fishless cycling add all the fish at once as it is safe to do so

 

[Kizz]

From what i've read once you've cycled your tank if you add too many fish at once you overload the bio on the filter and you get a spike cause the filter can't keep up with all the large amounts that it's not used to . As Long as here is fish or even food going into the tank this will still keep the beneficial bacteria in the filter

so in doing that your actually making your fish ill

 

[Truck]

thats the hole point in cycling! hw can you over loads your filter if you stock 1"per gallon after cycling you cant go wrong, ask any member that knows alot about cycling

 

[Kizz]

It overloads cause theres an overload in the ammonia and harmfull bacteria so the good bacteria which has not built up such a large colony is not able to destroy the harmful bacteria so if there;s an ammonia spiek you'll end up with ammonia burns and ill fish .

Yeah you do stock to 1" per gallon but if you have a 42 gal tank you can't put 42 1" fish or 21 2" fish in at once can you !

 

[Honeythorn]

In a newly cycled tank there will be enough bacteria to support as many fish that produce roughly the same amount or just a little more than the amount of pure ammonia you have been dripping in for a month. I DID NOT say don't add the fish at once. She can certainly add her current fish as there are only a relatively small number. The ammonia they produce will keep the colony in the filter going , and in a week she adds a couple more. Monitors the water, and the colony should adjust to take on the waste of 2 fishes worth of extra waste. and so on each week until fully stocked.

If you bung a load of new fish in immediately after the cycle is done you will effectively be dumping a load of ammonia in the tank, and the colony in the filter won't be large enough to cope with all the extra waste at once, so an ammonia spike will occur which can affect the health of the fish very quickly and cause illness. That's why you add slowly. To allow the adjustment in the bacterial colony.

 

[emilythestrange]

im worried about losing my existing fish from going to a 3-4 month old tank to a newly cycled one, yes that makes clear sense honeythorn, i was just wondering how the tank and fish will cope and wanting any suggestions. dont want to do any mistakes really.!

 

[Honeythorn]

afraid i cant use filter media because the little tank will be a home for a betta when my big tank is complete.

Ah right I see. Fair enough.

Live plants aren't difficult to grow in low or stock lighting by the way . Cabomba is easy, as is Elodia, Aponogentons, Java moss,Java fern, Moss Balls and Crypts.

 

[Honeythorn]

im worried about losing my existing fish from going to a 3-4 month old tank to a newly cycled one, yes that makes clear sense honeythorn, i was just wondering how the tank and fish will cope and wanting any suggestions. dont want to do any mistakes really.!

You could take out the filter in the small tank , squeeze out one of the sponges ( not both as you don't want to damage the cycle in your current tank ) over your newer filter media to boost the colony and speed the cycle up, and then put the filter back together and back in the small tank. A boost in the colony to eat up the ammonia is always good if you can manage it. As long as your Ammonia and nitrite reach and remain at 0 and your nitrates are low, you should be cycled at that point and can slowly add your fish without harm to them. Do a small water change after 3-4 days to make sure of no possible slight ammonia spike, and then do your regular weekly changes after that.

 

[Schmill]

At truckasaurus said above, that is incorrect advice as far as I know.

The ENTIRE point of fishless cycling is that you have a MASSIVE colony of bacteria grown in the filter.

At the moment in the OP's smaller tank that filter will have just enough bacteria to cope with the current fish stock that is in that tank. A sudden increase in stocking level in THAT tank would cause problems as you say due to the ammonia spike produced.

HOWEVER, when you do a fishless cycle you artificially create a MASSIVE ammonia spike (5ppm) and you sustain that level for a period of time, (at least for your qualifying week if not longer). This means that the bacterial colony in the filter in the tank that is due to be finishing cycling is MASSIVE at the moment and able to deal with a HUGE amount of ammonia in just 12 hours.
As long as you don't add fish that need a 'mature' tank, (a whole other issue!), then you can stock up to your 1" per gallon IMMEDIATELY in that tank as the bacterial colony is already there.
If you only introduce the fish from the other tank you will actually take a step backwards. the fish from the small tank won't produce enough ammonia on their own to sustain the large bacterial colony you have grown in the filter of the large tank, and as such they will start to die back. They will keep dying back until there is enough bacteria to process the levels of ammonia the fish are placing into the water. If you THEN go out to buy new fish you will only be able to add a few at a time to avoid ammonia spiking.

So your choices after cycling, are either:

A) All in, go out and get as many fish as you want in one go, (up to 1" per gallon), and add them all to the large tank
or
B) Add just your current fish, wait for a week, (all the time your bacteria colony is dying back), then go and buy a few more fish, and wait some time (for the bacteria colony to readjust to the new load), then buy a few more and wait.... ... .. ..

To be honest what I would do, (and what I am going to do in a week or two), is when the tank finishes cycling, go out and buy all the additional fish that you want, and introduce them into the new large tank, (I'm guessing there will be more 'additional fish' than there are 'current fish' ?) Then wait for a month, this will cover the quarantine period of the new fish, and then after that add your current fish across into the new large tank as well.

If you are only going to be buying a few new fish, (ie. LESS than you have in your tank at the moment), then I would do it the opposite way around and add your current fish into the new tank, and then add the new fish into your existing tank for a months quarantine. I don't image that this will be the case though as I'd think that you will buy more than just the equivalent of 3 guppies, 5 tetras?)

One other point to be aware of is that Tetras are one of the fishes that like mature tanks. We aren't really sure what changes between a 'freshly cycled tank' and a 'mature tank' (ie. running for 6 months+), but some people have reported that Tetras in particular are not good in freshly cycled tanks. Of course it depends on the strength / quality of the Tetras, and is completely up to you what you do, I just wanted to make you aware of all the info I was aware of.

 

[Truck]

thank you schmill.

 

[minxfishy]

Yep truck and schmill are correct, the whole point of a fishless cycle (apart from making sure the tank is ready for fish) is that the filter bacteria can cope with an immediate introduction of a (almost) full stocking of fish, as you have been adding 5ppm of ammonia for several weeks, therefore adding the fish is safe because its unlikely that even a full load of fish will produce that amount of ammonia in 24 hours time.

If after a fishless cycle, you only add a couple of fish then leave it a few weeks before adding more, the filter bacteria will have dropped back to only cope with those few fishes waste, so when introducing more fish, the bacteria has to re-multiply to cope with more waste.

 

[Truck]

you can't put 42 1" fish or 21 2" fish in at once can you !

yes you could in theory, because the size of the fish is generally proportional to the amount of waste given out.

a six inch oscar will produce more waste than 6*1 inch neon tetras, wont it? so that is the point in cycling.

emily if you do a cycle and follow it through correctly the tank will be fine with the stock you wish to put in.