Perhaps I'm even in the wrong place. You all seem to know so much. I'm an electrician and have no background in Biology, however, I love my aquariums. I've decided to set up an African tank for my first time. My aquariums have been set up forever, but I only recently learned about "cycling". My aquariums have always been very clean and have never required maintenance beyond a small weekly water change/gravel vacuum so this leads me to believe that I've probably achieved cycled tanks purely by accident.

However, this time I tried to follow instructions I've gathered from many different sources on the web.

My new 50 gallon tank is on day 31 of cycling. I haven't done any water changes for the past 3 days. My last change was a normal 10% water change done every 3 days in the first month of my tanks first cycle. Below are the measurements done prior to my tanks first major water change.

This is a table of the readings provided by both of the test kits I use to maintain my aquariums. The difference between master kits and sticks tests are pretty evident. Master kits will provide you with a more accurate reading, stick tests provide you with less accurate results but provides results extremely fast.

Here are the first test results prior to my first major water change:

Tetratest Laborett ( master kit )

NO3 n/a
NO2 - > 3.3 mg/l
NH3/NH4 - < 0.25 mg/l
pH - 8.3
GH - 16.0 (284.8 ppm)
KH - 10.0 (178.0 ppm)
CO2 - 1.6 mg/l
Chlorine - n/a

Jungle ( stick )

NO3 20.0 ppm
NO2 > 10.0 ppm
NH3/NH4 n/a
pH 8.4
GH 300.0 ppm
KH 300.0 ppm
CO2 n/a
Chlorine 0.0 ppm

** where there is n/a for reading indicates that the kit doesn't provide a test for that substance.

As you can see they don't exactly match but the stick kits are never very accurate and should probably only be used to quickly look for any indication of a potential problem, then if something is indicated by the stick tests you can go ahead and pull out the master kit, clean your vials, collect your samples, and wait for more accurate results.

Okay. So, where were we? .. ok - I remember now. 50 gal. aquarium, day 31 of it's very first cycle. So, today we (we as in I) are going to perform a heavy cleaning of the gravel areas where debris collects and do a 50% (25 gal.) water change then I'll test the tank again and compare the results.

1 hour later...

My gravel is now clean, my tank is re-organized slightly, and my water has been refreshed with treated tap water of the proper temperature to lessen the stress on my fish. Now I wait and let my tank settle for a few hours before testing again.

A few hours later...

Okay. Now I can go ahead and perform my tests. I wait a few hours for several reasons:

1) to allow my water to mix and be cycled through the filter plenty of times.
2) to allow the small particles I stirred up in the water to settle back into the gravel.

I want the water I test to be a good indicator of the current state of my aquarium in it's normal state. Not it's state after a hurricane, which is how it gets when I clean it.

Here are the results after my first major water change:

Tetratest Laborett ( master kit )

NO3 n/a
NO2 - 0.3 mg/l
NH3/NH4 - < 0.05 mg/l
pH - 8.3
GH - 11.0 (195.8 ppm)
KH - 10.0 (178.0 ppm)
CO2 - 1.6 mg/l
Chlorine - n/a

Jungle ( Stick )

NO3 < 10.0 ppm
NO2 < 10.0 ppm
NH3/NH4 n/a
pH 8.4
GH 150.0 ppm
KH 300.0 ppm
CO2 n/a
Chlorine 0.0 ppm


So, Nitrite levels have went from greater than 3.3 mg/l to 0.3 mg/l a definite drop but still enough Nitrite is present in the water to be detected. Ammonia levels dropped by .2 mg/l. General Hardness of my water also dropped for some reason, this could be due to the rocks in my aquarium. pH levels and CO2 remained steady. Of course, no Chlorine is present because I treat my water before I add it to my aquarium. Finally, the stick test could still detect enough Nitrates to change colors, but not enough was present to turn it the color that would indicate 10 ppm was present so I marked it as less than 10 ppm Nitrates.


Okay, now that I've provided as much information as I possibly can. My questions are -


1) is my aquarium cycled?
2) is there anything in my data that indicates I've done something wrong?
3) if not, how soon can I remove the stock I've used to cycle the aquarium and replace them with african cichlids?

No your tank is not cycled yet but I think your getting very close. When it is finished cycling you will have readings something like Ammonia 0, Nitrite 0 & Nitrate 10ppm. It doesn't look like you have done anything wrong for a fish in cylce, I think you just need to be a bit more patient until there is 0 ammonia & nitrite & some kind of positive reading for nitrate. Once you have numbers like that it will be time to remove your cycling stock & add in your cichlids. After you add the cichlids keep an eye on the test results to make sure you don't get an ammonia or nitrite spike.

__________________
4 x 180gal, 3 x 120gal, 3 x 65gal, 4 x 55gal, 3 x 20gal, 2 x 15gal, 4 x 10gal, 4 x 5gal. Everything from rift lake & american cichlids to many community tropical species. Planted & non planted tanks.

Ammonia (NO3/NO4) tested below the chart I have to compare the color of my test tube against but it did slightly change colors. The lowest possible comparison was 0.0 mg/l but since there was a very slight change in color I marked it as less than 0.05 mg/l so there is virtually no ammonia left in my tank, even 16 hours later when I tested again and achieved the exact same results.

Nitrite (NO2) definitely tested at precisely 0.3 mg/l both last night and this afternoon (approx. 16 hours later). So if I'm aiming for 0.00 mg/l NO2 then I have some waiting to do I guess.

Nitrate, however is very close and I suppose this is a good thing because these are the bacteria I want present in my tank right? So, there is still some biology left after the major water change to continue the biological filtration cycle?

Lastly, I have a clown loach and a bristlenose pleco that have shared my grow-out tank with the few africans I have at the moment. Will this clean-up crew continue to be safe in the new tank as the africans get a little larger?

Thanks so much for any help.

-johnny

Just an update.

10 days later, here are the results.

Tetratest Laborett ( Master Kit )

NO3 - n/a
NO2 - 0.0 mg/l
NH3/NH4 - 0.0 mg/l
pH - 8.2
GH - 11.0 (195.8 ppm)
KH - 10.0 (178.0 ppm)
CO2 - 1.6 mg/l
Chlorine - n/a

Jungle ( Stick )

NO3 - 10.0 ppm
NO2 - 0.0 ppm
NH3/NH4 - n/a
pH - 8.4
GH - 150.0 ppm
KH - 180.0 ppm
CO2 - n/a
Chlorine - 0.0 ppm

You were right .. I just needed to get over the hump I guess. Patience won the day. Thank you for the help.

- Johnny