Q-Tank Cycling Question

Beverly · #1 03-04-2004, 09:42 PM

This is a dumb question that I should know the answer to, but am unsure of.......

I set up a bare 20g Q-tank two months ago. It has a heater, glass lid, an NO light of some sort, pvc elbow and T, two small powerheads, and an AquaClear Mini and AquaClear 200 both filled to the max with foams for maximum surface area for bacteria growth. Fed it heavily for use with two fish. Cycling seemed to take forever, but it finally cycled.

Okay, then, the tank cycled. I cleaned out all the algae, cleaned the foams in outgoing changewater and did a 100% water change. Put in the two fish that had been in my 72g tank of doom where the fish had ich off and on.

Fish have been in the Q-tank for over a week, no sign of ich. Hooray!!

Dang. Once I put the fish into the tank, I got .4 ppm ammonia and .2 ppm nitrite the next day. Have even been suctioning out all leftover food and poop. Had been doing twice daily 50% water changes to keep the fish eating, but then remembered that adding Prime would neutralize the ammonia, so I've been doing that daily and skipping some of the big water changes. Fish are eating well, no signs of ich. Hooray!!!!

Anyway, my question is this: Prime converts ammonia to ammonium. Are the same bacteria that process ammonia into nitrite the same as the bacteria that process ammonium into nitrite? I'm pretty sure the answer is YES, but I need to check this out.

TIA

sleeman · #2 03-05-2004, 01:33 AM

Beverly,
From what I understand, you are correct. Prime will neutralize, but nitrosomonas etc will still feed on the ammonium. I use prime as well when my q tank gets away, and have never had any problems.

Cheers,

Al

Lofus · #3 03-05-2004, 02:23 AM

Beverly,

I think the 100% water change and cleaning the foams probably eliminated most of your bacteria. The bacteria need the "dirty" water to feed.

That's why you need to feed the tank beacuse without the amonia source no bacteria will be established.

Beverly · #4 03-05-2004, 02:31 AM

The tank was cleaned and the water changed the day before the fish went in, so the bacteria would have still been in the foams, don't you think? Also, it's impossible to fully clean foams, no matter how hard a person tries. There would have been some detritus in the foams to keep the bacteria going for the day there was no fish or food in the tank.

EmilyB · #5 03-05-2004, 03:01 AM

I agree about the 100% water change and depletion of bacteria from the foam - it's certainly not something I would ever do anyway.

Even if you didn't kill all the bacteria Bev, if the tank was cycled, something was supplying them with food. The remaining bacteria could not handle it.

Beverly · #6 03-05-2004, 12:15 PM

Quote:

Originally Posted by EmilyB

I agree about the 100% water change and depletion of bacteria from the foam - it's certainly not something I would ever do anyway.

Interesting how folks say what they would not do, but do not offer what they would do instead

Please enlighten me as to how you would cycle a a bare tank that will possibly be used to treat ich (or other diseases), then get it ready for occupancy. Also enlighten me on the care of the tank once the fish are in it for a 6+ weeks for treatment (probably hyposalinity), to keep nitate low when foams have already become nitrate factories.

Keep in mind that the tank had been moderately fed for 2 months with fish food, had lots of cyanobacteria on glass and pvc, and nitrate levels of 10-15 ppm.

StirCrazy · #7 03-05-2004, 01:08 PM

[quote="Beverly"]

Quote:

Originally Posted by EmilyB

Please enlighten me as to how you would cycle a a bare tank that will possibly be used to treat ich (or other diseases), then get it ready for occupancy. .

do a water change on your biggest tank and use that aged water to kick start your quarantine tank. from that point 50% water changes as needed to control your nitrates in your q tank if and when they start to raise.
use your filtration and carbon if you are not medicating.

Steve

Beverly · #8 03-05-2004, 01:37 PM

Steve,

How would adding water from an established tank kick start the cycle in a new tank? Not trying to be contrary here, but all I would get from the other tank would be water with about 10-15 ppm nitrate and slightly low alk/Ca (common before weekly water change in my tanks), and no bacteria since bacteria typically do not live in the water column but live on surfaces in the tank. Also, if the established tank is cycled, there would not be any ammonia or nitrite, so I don't see a benefit from using water from an established tank for that reason either.

I must not be seeing the benefits of using old tankwater the way you see them....

Lofus · #9 03-05-2004, 06:06 PM

The biggest advantage to using existing tank water is that the water chemistry in the QT will very closely match that of the Main tank so it will minimise the adjustment needed by the fish when they come out of the QT.

The other benefit is that the existing tank water is already laden with the biological residue that decomposes into Amonia and Nitrite so you can start growing both cultures right away.

Starting from scratch on a QT, I would use 50% main tank water and 50% new water (my QT is 30 gal so I would have to do a 50% water change to the Maint tank to fill it. This would stress my main system too much).

I feed the tank with a coctail shrimp to provide amonia. To jump start the process I have taken a small babyfood jar of sand from the tank and placed it in the QT. (Keeping the sand in the jar since the QT is bare bottomed.)

Once the tank has cycled, I check the Nitrates. I then perform 10-20% water changes using main tank water over the course of a couple of days to get the nitrates under 10ppm. While the tank is up I do a 10% water change every week using water from the main tank.

As an added bonus my main tank gets lots of fresh seawater in small doses over time.

I do not clean anything except the glass in the QT until I empty it.

I hope that helps.

Jim

Beverly · #10 03-05-2004, 06:35 PM

Jim,

Sounds like a good plan for a Q tank. But for a tank that harbours ich, like mine, not so good. Luckily, I got my fish out of the main tank while they had no ich, so I'm thinking I may not have to treat for ich, just QT them for 6 weeks.

Actually, it may be more than 6 weeks, because I think your idea of doing water changes from the main tank into the Q tank is a good one. Once the main tank has been fallow for 6 weeks, I may do several 20% water changes over the course of 3-4 days to easier acclimatize the fish to the main tank.