Why won't my tank cycle?

[laurabb]

I have a 2.5 gallon tank with one betta in it. I know it's a small bioload, but this tank won't cycle. At all. It's been set up for 8 weeks with the betta, and there are still no traces of nitrites or nitrates yet. Before the grandparents "surprised" the kids with the betta, I'd been trying to do a fishless cycle with ammonia for over 11 weeks, and again with no sign of nitrites or nitrates developing. (I cleaned the tank thoroughly when the betta arrived). So we're doing a fishy cycle.

I check for ammonia 2x daily, and change the water whenever it hits .25. On occasion I've done a water change at night, had the ammonia read 0, and then have awoken the next morning to a tank that's at .50 or above. Lately, the ammonia level has been at 0 for 3-5 days at a stretch, but there are still no signs of nitrites or nitrates. I don't get it.

Is this totally unheard of in small tanks? I don't mind monitoring the tank so closely, but someday I would like to go on vacation and know that we have a cycled tank that would be OK for a few days without twice daily monitoring.

I use the API master test kit, and use a drop of Prime per gallon as a water conditioner. Could the Prime be masking the nitrite and nitrate readings? I guess that doesn't make sense, because it certainly picks up the traces of ammonia.

Any ideas?

 

[ct-death]

IME the smaller the tank generally the longer the cycle. Don't ask me why :shrug:

You are doing everything perfectly it sounds. Do you have another tank up and running you could use some material from? Or a friend? Seeding the tank would be the fastest way to get it going.

I'm assuming that this tank is filtered and has gravel, etc.?

BTW - FWIW; My wife keeps bettas (unfiltered, but heated tanks). She just does a 100% water change(WC) and gravel rinse every 10-12 days... NOT what I would recommend, but she has similar size tanks (I'm not allowed to touch her bettas...)

 

[Subliminal]

Yeah, if you have no gravel or media for the bacteria to live in, it probably won't cycle. You didn't mention that, so it's hard to say w/o knowing...

Generally I think betas are kept like ct mentioned above. In bowls or whatever in situations where full water changes are performed regularly.

 

[laurabb]

The tank is heated, and has a filter. It also has smooth flat marbles as a substrate. The marbles are easy to vaccuum, and the betta likes to lie on them sometimes (or push them around with his nose). Are the marbles the reason my tank won't cycle?

 

[Star_Rider]

no the marbels if anything will be a place for the bacteria to settle.

just curious..how often do you clean the tank and how do you clean it.

are you changing filter material out?

 

[kimmisc]

I have a 2.5 gallon tank with one betta in it. I know it's a small bioload, but this tank won't cycle. At all. It's been set up for 8 weeks with the betta, and there are still no traces of nitrites or nitrates yet. Before the grandparents "surprised" the kids with the betta, I'd been trying to do a fishless cycle with ammonia for over 11 weeks, and again with no sign of nitrites or nitrates developing. (I cleaned the tank thoroughly when the betta arrived). So we're doing a fishy cycle.

I check for ammonia 2x daily, and change the water whenever it hits .25. On occasion I've done a water change at night, had the ammonia read 0, and then have awoken the next morning to a tank that's at .50 or above. Lately, the ammonia level has been at 0 for 3-5 days at a stretch, but there are still no signs of nitrites or nitrates. I don't get it.

Is this totally unheard of in small tanks? I don't mind monitoring the tank so closely, but someday I would like to go on vacation and know that we have a cycled tank that would be OK for a few days without twice daily monitoring.

I use the API master test kit, and use a drop of Prime per gallon as a water conditioner. Could the Prime be masking the nitrite and nitrate readings? I guess that doesn't make sense, because it certainly picks up the traces of ammonia.

Any ideas?

If you cleaned the tank thoroughly when the betta arrived, you started over completely with the cycle. You're now at 8wks with the cycle, and the previous 11 weeks no longer count.

I understand your frustration about the cycle. I ended up doing a fishy cycle on my 29gal that wouldn't budge for over a month too. That was ALOT of toting water everyday, not to mention tons of stress for the fish.

I finally gave in and ordered some bio-spira from drs foster and smith online. It kicked the cycle right into gear.

Advice if you decide to get some: You'll need to dose it twice, so either get 2 small pouches, or save about 1/2 of it to add once you get nitrites, else the nitrite eating bacteria die by the time they have nitrite to feed on. I can vouch for this. I had to order a second batch because I was stuck in the nitrite spike after only using one dose. When adding the bio-spira, pour it directly into the filter.

After the first dose, it will take a few days for the nitrites to show up. It takes a bit for the bacteria to settle down, colonize, or whatever. My nitrites showed up 3 days after the first dose.

 

[ct-death]

Gravel vac, very carefully - just enough to get the loose flakes and poop on the bottom. The smooth surface of the marbles offer plenty of purchase for the bacteria, but it's not like a rock with crevasis, angles, etc. Also gravel may have easily 3x the surface area as a marble the same size.

Your fine, just vac gently until your cycle is done. You wont have a lot of buildup with only 1 betta anyays. I think my wife feeds hers a small dose once every 3 days (they are floating grains and she skims them out after 2 hours)

Hope that helps!

 

[laurabb]

no the marbels if anything will be a place for the bacteria to settle.

just curious..how often do you clean the tank and how do you clean it.

are you changing filter material out?

I change the water ~ 30-50% whenever the ammonia hits .25 ppm. Sometimes that's twice a day, or more likely, once every day or two. Right now we're in a phase where the ammonia seems to take 3-5 days to build up, so lately there are fewer PWCs. I also gravel vac with every water change. I think I'm vaccuuming pretty gently - the betta comes right over to the vac and plants himself there, and sometimes I have to give him a nudge to get him to move. I've taken out his cave and silk plant maybe 2-3 times to vaccuum the tank floor, and rinse the cave and plant in old tank water that I've siphoned out. I don't have algae or anything like that, so I haven't had to clean the sides of the tank or anything. I did wipe down the heater one time with a paper towel, because it was getting this yucky white film on it. I don't touch the filter media, other than to check it over for any crud (never anything in there), and I have changed the carbon pad 1x a month (this is a Red Sea Nano filter). I've since read that I don't really need the carbon in there, so I guess I'll take it out with the next water change. I don't think I'm keeping the tank "too clean". Or am I?

 

[kmail5776]

You may have ammonia bacteria building up, but you have to watch for nitrites now. This will build up as ammonia drops. Nitrite is lethal in smaller doses compared to ammonia, since it works by inhibiting oxygen intake. Keep up with the partial water changes every day and get a test kit to test for nitrite.

You can never keep your tank too clean.

 

[klfvilla]

I have a 5 gallon with a betta and a dwarf platy. My tank is now 5 weeks along. I can't test for ammonia because I have bleachy city tap water which gives a false positive even after adding conditioner. I am just now seeing .25 nitrites and no nitrates yet. I'm doing pwc when I see nitrites and hoping that things will move along ... eventually...