Cycling woes

[richardh]

Ok this is getting rediculous now. Had my 65 litre / 17usg tank up and running for 14 weeks now and I am still having cycling issues. It was my very first tank and I did a fish in cycle (I know, I know). Anyway...

Ammonia readings have been zero and stayed zero for about 10 weeks, but I cannot get my nitrites down to zero and keep them there. Levels reach 0.5ppm in around 4-5 days after a 50-75% PWC. NitrAtes seem stable around 5-10ppm. I never let levels get above 0.25.

Admittedly I have played around with stock. Currently have 3-guppy, 5-glowlight tetra, 5-cardinal tetra, 2-oto, 2-Pygmy cory, 1-golden apple snail. Probably slightly overstocked? I could rehome the tetra if need be...

Do you think I have enough filtration? The internal filter (aqua one 102F) came with the tank and is supposed to be ok for larger tanks than mine (75litres), it has a turnover of 500 l/hr.

What the **** is going on! I am pulling my hair out. I don't understand why it is not settling down. In the time i have had this tank, i have set up a 33usg AND seeded it using the 17!! The 33 is rock steady, fully cycled, so I don't get why the 17 won't fully cycle. Any suggestions please before I give it up as a bad job...

 

[librarygirl]

How long have the nitrites been present? The nitrite phase is the longest of the phases; it can take an average of 3 weeks for them to zero out. Plus if you kept adding fish during that time the bacteria would need to constantly adjust to the higher load so the phase would be prolonged.

Also you are overstocked for your tank; I think adding too many fish too soon is part of the issue as to why it's taking so long. Stop adding fish and keep up with water changes, it should settle down eventually.

 

[richardh]

Nitrites have been showing up for the last 9 weeks! I get them to zero by PWC and then 4-5 days later they start showing up again. This makes me think the filter is not up to it?

When i started, i did a fish in cycle with 5 red eye tetras and thought I was there. I moved the red eyes into my 33 and replaced them with 10 cardinals, so this would have reduced the load slightly? 5 died though due to bad stock. Glowlights were added a few weeks ago when again I thought I was cycled. But nitrites kicked in again and don't seem to be going away this time - 3 weeks now...

I don't intend to add anymore fish to this tank. I am think of removing the glowlights and rehoming them at the next PWC. This maybe will help with the bioload?

 

[librarygirl]

It's possible there isn't enough filtration; generally you want to double the filtration for the size tank, so for a 17 gal tank you want a filter that is large enough for at least a 35 gal tank, a 50 gal would be better. Plus the overstocking probably hasn't helped. Can you add another filter? So you have a larger established tank? Any chance you can pull some media from that tank and add it to a new filter?

I'm guessing that other than changing fish you haven't changed out any filter media, right? Or washed it in tap water? And you're using dechlorinator with water changes?

The only things I can think of are too much fish in a tank that wasn't completely cycled and that doesn't have enough filtration. If you can move out some fish and add another filter that might help things.

 

[richardh]

Thanks for the advice, yes I probably rushed things a little. You live and learn....

I have only cleaned the filter cartridge once in tank water and I am little scared to! I always use dechlorinator, so no schoolboy errors...

I have a 33g that has been fully cycled for about 5 weeks (0 amm, 0nitri, 10 nitrate). I suppose I could squeeze one of the sponges from this into the 17g to help. I will also rehome the glowlights to help with the overstocking.

As for replacing the filter, I don't know. As its such a small tank, a huge filter might take up too much room. I can look at other options.

Thanks again for the suggestions

 

[Phranque]

Ok this is getting rediculous now. Had my 65 litre / 17usg tank up and running for 14 weeks now and I am still having cycling issues. It was my very first tank and I did a fish in cycle (I know, I know). Anyway...

Ammonia readings have been zero and stayed zero for about 10 weeks, but I cannot get my nitrites down to zero and keep them there. Levels reach 0.5ppm in around 4-5 days after a 50-75% PWC. NitrAtes seem stable around 5-10ppm. I never let levels get above 0.25.

Admittedly I have played around with stock. Currently have 3-guppy, 5-glowlight tetra, 5-cardinal tetra, 2-oto, 2-Pygmy cory, 1-golden apple snail. Probably slightly overstocked? I could rehome the tetra if need be...

Do you think I have enough filtration? The internal filter (aqua one 102F) came with the tank and is supposed to be ok for larger tanks than mine (75litres), it has a turnover of 500 l/hr.

What the **** is going on! I am pulling my hair out. I don't understand why it is not settling down. In the time i have had this tank, i have set up a 33usg AND seeded it using the 17!! The 33 is rock steady, fully cycled, so I don't get why the 17 won't fully cycle. Any suggestions please before I give it up as a bad job...

Well, not to be too much of a smart a$$, but you kinda answered your own question.....

That is a decent stock for that tank, but too many for fish-in cycling, IMO. I'm not a huge fan of in-tank filters... would prefer a small canister (Fluval 1 series would probably be good, 2 series even better), but what you have should work, but might just take a bit longer to cycle, as you are observing. Big thing is being patient & quit messing around with your stock.... let things settle.

 

[richardh]

It often helps to just get it down in black & white, then you can see it staring you right in the face

I am going to reduce the stock though and add more seeded media, just to help out

 

[Phranque]

Patience, patience, patience...... If you don't have it, this hobby will either teach you, or put you on blood pressure meds.