Q's on The Fishless Cycle

[newland]

Hi All

I've been reading all about fishless cycling and as i'm about to go through it for the first time. I'm very wary about stocking my entire tank after the process is completed.

So i've had a mini thought about the fishless cycle.
Can the fishless cycle be used to prevent mini cycles when adding new fish to your tank?

If you have a tank with say half stock can you then slowly start adding small amounts of ammonia into the tank to boost the bacteria growth. As this would be done slowly over a period of time the basteria would be able to grow without causing a mini boost.

Any one tried it or is this just a load of crap?

If its not a load of crap and could work then i'm going to try it as i'm in the process of setting up 2 new tanks. So i'll stock one at 1/2 and one at full.

Then on the second tank i'll try preventing a mini cycle.

 

[rdd1952]

I wouldn't try that. The main reason being, the amount of ammonia any new fish would create will be much less than what you would add manually unless you're only talking a drop or 2 and then that will take quite a while to actually build any bacteria. Also, if you happen to overdose, you might kill the fish you already have.

 

[gadazobe]

The amount of fish you can add after doing a fishless cycle depends on the amount of amonia added during the cycle. If you added quite a lot of amonia, then the beneficial bacteria produced will be sufficient for a full tank of new fish, whereas if you added very little, then less beneficial bacteria would have been produced, meaning less fish. Do I make myself clear?

And it's not advisable to add amonia with fish in the tank.

 

[Slyspy]

If you added the recommended amount of ammonia through out your cycle (is it 5ppm I forget?) then there is no problem adding a full load of fish. The bacteria bed will be able to cope, since that is far more ammonia than even a full load of fish can produce. Do not worry about adding your fish, there will be no mini-cycle so long as you keep feeding the bacteria right up to the point you add your fish. If anything adding too few fish will encourage a mini-cycle. I would discourage you from adding ammonia yourself once stocked since you may add more than the fish can cope with, though the bacteria will love it!

 

[newland]

cheers everyone for the information.

I was thinking that this may be a good idea but i guess i was wrong.

oh well.

I'm going to do the fishless cycle and add a full stock to one tank then if thats ok i'll do the same for the other tank too.

 

[Macracantha]

The point of a fishless cycle is to not subject fish to the ammonia and nitrite...therefore I wouldn't want to be adding it in myself once I'd started stocking!

 

[newland]

I don't think i made myself clear enough on my origional question.

What i was going to do was add small amounts of amonia to act like more fish have been added with out actually adding more fish.

This amount would be small in quantity slowly increasing in amounts that the filter could cope with.

I wasn't thinking of adding a lot of amonia at once but a little to boost bacteria production.

The idea being that the fish don't notice a change in amonia but the bacteria grow to cater for a higher waist content. therefore i could add more fish in one hit would out adding 2-3 then waiting x weeks. then adding 2-3 more.

Its all a sugestion and i was wondering if it could be done/was benifitial.

The idea of having a half stocked tank and then adding 7 fish in at once does not seam a good idea to me. surely this would be worse for the fish.

The main reason for asking this question is my fish shop is quite a drive so i don't really want to going back and forth every other week.

 

[rdd1952]

Adding the ammonia a little at a time like that is definitely something you can do and probably build some extra bacteria but as I said earlier, I wouldn't do it. You would be better off adding the 6 or 7 fish and having the little mini cycle. If you're adding small amounts of ammonia, how will you know how to add, how much extra bacteria you have built up, whether it's enough to support 4 fish or 10 fish? You will just be playing a guessing game. I would prefer to have a small mini cycle when I add more fish than to keep my tank in a constant mini cycle by adding ammonia.

 

[Macracantha]

Adding the ammonia a little at a time like that is definitely something you can do and probably build some extra bacteria but as I said earlier, I wouldn't do it. You would be better off adding the 6 or 7 fish and having the little mini cycle. If you're adding small amounts of ammonia, how will you know how to add, how much extra bacteria you have built up, whether it's enough to support 4 fish or 10 fish? You will just be playing a guessing game. I would prefer to have a small mini cycle when I add more fish than to keep my tank in a constant mini cycle by adding ammonia.

I agree!!!

As I said...I don't see any sense in adding ammonia to a tank with fish already in!

 

[sinistral]

Actually...I don't think this is such a bad idea on paper. When you are adding a new load of fish, you are in essence "adding ammonia to a tank with fish already in". I wouldn't be inclined to dismiss an innovative idea-- somebody had to think of the fishless cycle, which was an enormous innovation at that time. The point would be to see if it is feasible in practice and to refine the process to make it as efficient and safe as possible for your existing and incoming fish-- safety being the most important consideration.

Off the top of my head, the way you would have to go about it is add an arbitrary (but small!-- probably 10%, conservatively, of the amount you added for the fishless cycle in the first place) quantity of ammonia on day 1 and test. You should be shooting for a quantity that does not change your reading at all. If you got an ammonia reading, you would have to cut back. On day 2, you would add that quantity from the day before, plus another small quantity (another 10%?) and retest. This is very rough, but I would imagine you would keep readding incrementally larger quantities until you get a small bump in ammonia (0.25, let's say on the reading). You might do a small water change at that point. Then on subsequent days, you would continue adding that amount until you get no increase in readings. At that point, you know that you are pushing the limits of what your bacterial bed can tolerate. Continued increases in this way would be expanding what your bacterial bed can tolerate. At this point, you would also want to be testing for nitrite and checking nitrate levels as well, so's not to cause fatal levels of toxicity.

In this way you could expand the growth of the bacterial bed with minimal damage to the fish. The tank would then be ready for a new supply of fish.

This begs several questions-- almost too many to discuss. For one, how do you estimate how many fish the tank is ready for? I think a decent model would be to compare the maximum quantity of ammonia you can add to the tank to the original amount of ammonia you were adding to complete the fishless cycle. If you end up adding about half the ammonia, your tank would be ready for half the original bioload. In practice I have no idea if this would be accurate.

Another question would be-- is adding half again the original bioload of fish advisable? Are there other questions of territoriality or living space to consider? Is this process safer and more efficient then simply adding a couple of fish at a time to minimize ammonia toxicity?

Also, how do you know what endpoint of ammonia you are shooting for? Do you want to add about 50% of the ammonia you added (2 or 3 drops, for instance) initially during the fishless cycle? It would not be such a bad thing to get bacterial overgrowth if your estimates are off, but undergrowth would be a bad thing for the fish.

Finally, would this process even be efficient? In practice, how quickly could this take place? Is it safe? Would the bacterial organisms behave unpredictably under these circumstances?

I don't claim that these thoughts are authoritative-- in fact, they are purely what I thought of this very moment and are probably subject to further modification. It *could* be a failed idea, but again, I wouldn't be quick to dismiss something which could be a significant modification of the original fishless cycle idea.