Mini Cycle

[Lawsman]

So, I replaced a useless Marineland C220 with an FX5 today. I have a big w/d with two Mag 5's and Korila 4. My question/concern is will the tank see a "mini cycle" by the addition of FX5? I know there is plent of beneficial bacteria in the tank so the new FX5 will seed quickly, but not sure if cause a mini spike in water parameters (ammonia and Nitrite)?

Or....am I just paranoid

[mgarrido]

how you know this: "I know there is plent of beneficial bacteria in the tank". Did you test your water parameters? what is the nitrate levels and for how long time your take is cycling? also how are you cycling your tank? i would keep using the marineland filters if is the one with the beneficial bacterias or use that media in your new filter.

[Lawsman]

Yeah, I tested the water last night. This is when I discovered the Marineland was not flowing any water. Nitrate about 20, everything else 0. The tank and w/d with two Mag 5's has been running for over two months now. Also, used the African "alive" substrate stuff when initially set up. No fatalities with my Red Rainbow colony. I would like to keep it this way.

Initially, I cycled the tank with Stability for one week prior to colony arrival. All water parameters were okay. I put some more Stability in the tank, but don't really know if I'm doing any good?

I did not use the bacteria in the Marineland becasue it may have died due to lack of flow-oxygen????? I don't really know, seemed to make sense to me, but looking what more experienced people think or would do in my situation?

So, I don't know if I will have a mini-cycle? Guess I will just have to test water daily and do W/C's if necessary?

[Complexity]

Personally, I wouldn't worry too much about a mini-cycle. Check your water daily for spikes of ammonia or nitrites and to see if the nitrate levels continue to rise. Do not add any new fish at this time and do not overfeed the fish. If you do run into a mini-cycle, step up on the water changes. You should be fine in a week or so. Once your tests show 0 ammonia, 0 nitrites and an increase of nitrates, then you know you're in good shape.

[Lawsman]

Vicki,

Okay. Thanks! I will keep my test tubes out! Just tested for Nitrate, they are 10!!!!!!!!! Good idea about minimizing the feeding. Did not think about that?

[Complexity]

Don't just test for nitrates. Test for ammonia and nitrites, too. You need to be sure they stay at 0. It is possible to have bacteria converting everything into nitrates, but not enough bacteria, leaving ammonia and nitrites in the tank. It is only after you have ensured that ammonia and nitrites stay at 0 while the nitrates are rising can you be assured that the tank is fully cycled.

[Lawsman]

10-4. Will do all three tests-Thanks. Did not know it was possible to covert everything directly into nitrate, leaving possibility of ammonia and nitrites. Good stuff!

[imagirlgeek]

You said you have a W/D on the tank? You probably won't see a cycle at all if you're running a W/D. That thing is full of beneficial bacteria if it's been running for a while.

[Zulaab]

+1 for everyone above :)

[Lawsman]

Yep, did some water testing this morning before work- Ammonia 0, Nitrite 0, Nitrate btw 10-20ish. All good. Must be wet/dry and Stability? Oh and the Ph was 8.2

[Complexity]

10-4. Will do all three tests-Thanks. Did not know it was possible to covert everything directly into nitrate, leaving possibility of ammonia and nitrites. Good stuff!

Just to clarify so what I had said is not misunderstood, I was referring to a balance between bacteria and the amount of ammonia (and the subsequent nitrites). Let me put some numbers to better explain what I mean. These numbers are only to explain the concept and have no actual value.

Let's say you have 500 bacteria that convert the ammonia into nitrite. I'll call them 500-I bacteria.
And let's say you have another 500 bacteria that convert the nitrite into nitrate. I'll call them 500-A bacteria.

You fish poop out 500 ammonia rations. Your 500-I bacteria convert that into 500 nitrite rations. And so now your 500-A bacteria convert that into 500 nitrate rations. Cool.

Take away 100-I bacteria.

Your fish poop out 500 ammonia rations. Your 400-I bacteria convert that into 400 nitrite rations, leaving 100 ammonia rations in the tank.
Your fish poop out another 500 ammonia rations. Your 400-I bacteria convert that into 400 nitrite rations, leaving an additional 100 ammonia rations in the tank. Now the tank has 200 rations of ammonia left in the tank.
The 400-I bacteria cannot convert the left over ammonia into nitrite because it's busy converting the next round of 500 ammonia rations being pooped out by the fish. The ammonia rises.

Of course, in this process, nitrites are being created which the 500-A bacteria eagerly convert into nitrates. So what do you have? A rise in nitrates AND ammonia. (Of course, this could apply to nitrites, as well.)

The solution is for the 400-I bacteria to multiply until it reaches 500-I. Once it does that, it can handle the 500 rations of ammonia being pooped out on a regular basis. That means all the ammonia is being converted into nitrites (and then nitrates), dropping the ammonia reading down to 0. It remains at 0 because there is enough bacteria to handle the constant load of ammonia.

This is a mini-cycle. It is different from a full cycle in that bacteria is present in the tank, but not in sufficient quantities to handle the full load of ammonia being put in the tank. This can happen anytime extra ammonia is suddenly added (a can of food is accidentally dumped into the tank) or the bacteria is suddenly reduced (large bacteria colonies are removed due to excessive cleaning or loss of filter as in this case).

As long as as the alteration of the added ammonia or the subtracted bacteria isn't too great, the tank usually remains cycled as the bacteria multiply rapidly to make up for the difference. But if there is a large difference, the bacteria may not be able to multiply fast enough to keep up. In that case, ammonia and/or nitrites can rise high enough to become a problem. This cannot be detected by only measuring the amount of nitrates in the tank because some of the ammonia is being converted into nitrites. The presence of nitrates does not negate the presence of ammonia or nitrites.

The solution is then to reduce the ammonia and nitrites in the tank by lowering the amount of food being fed (fish cannot poop what they cannot eat) and to perform extra water changes until the bacteria multiplies sufficiently to keep up. Simple enough.

For the most part, mini-cycles are not a big issue. When I clean my canister filters, I clean them thoroughly to the point that I know I'm killing/removing almost all the bacteria in them. My tanks remain stable because I always run 2 canisters and never clean out both at the same time. So even with the complete loss of the bacteria from one of the two canisters, the tanks remain stable. There is enough bacteria in the second canister and in the tank itself to compensate. That's left multiplies fast enough to keep up with the ammonia and nitrite load. In your case, it appears your W/D compensated in the same way.

[Lawsman]

Got it. Had to read it a few times, I'm a little slow as I age. But, understand the concept now, which was really my original question. Yes, It does appear the W/D compensated-it does have good flow.

I like the idea of only cleaning one canister at a time. Makes sense. Today is a good day-I learned something new.
Thanks

[Complexity]

You're welcome! I'm glad I could help.