High nitrite/nitrate readings

[jim LI]

i have a 72 gallon tank, 1" sand substrate, 2 years established. 9 adult discus. I am medicating with metro for a case of hex, mediating for 2 weeks, double dosage, twice a day. i do 60% wcs everyday. 2 - 2217 filters. my normal parameters are ph - 7.2 -7.6, ammonia - 0, nitrite - 0, nitrate <5. i changed out the filter floss over the weekend, not the media, from the canisters. i use aged water for w/cs. before a w/c, my nitrites are now running >1, nitrates >10, ammonia - 0. after a wc, nitrites - .25, nitrates <5. but they go right back up over night. i know i could be going through a mini cycle, but i have never had a mini cycle affect the nitrites that much. i use safe and according to seachem, i can 4 times the dosage in emergencies, which i am doing, to detox the nitrites.

my questions - should i stop feeding the fish for a couple of days to reduce the nitrites?
is the metro affecting the nitrites?
can 1 of the fish with hex be affecting the nitrites?
can i add anything to the tank, like stability?

thanks for your help,
jim

[HarryDk]

hmm, i feel like you messed up your biofilter somewhere along the way? has there been any low PH reading? over clean filter media? anti-bacterial medication?
i'm not sure if metro affect nitrate but metro is sugar base, will spoil the water quickly.
Stability won't hurt but work or not, we never know :|,
SAFE and PRIME are your best friend during mini cycle imo, more wc ... good luck.

[jim LI]

thanks,,,, i also tried aquarium salt, some posting say it will help with treatment... my nitrates shot up to 5 over night after the first dose of salt. so i stopped that. i also stopped metro and stability... i am going back to my normal routine.. 2 x dose of safe.....but it is now almost 3 weeks since i did the filter clean and i am still not back to normal.. can anyone suggest anything else i over looked? it is getting quite frustrating.

thanks,
jim....

[Second Hand Pat]

Hi Jim, test your tap water.
Pat

[jim LI]

Thanks Pat. Here are my reading

Tap water - ph - 7. ammo - 0, nitrite - 0, nitrate -0

Tank before w/c - ph - 7, ammo, - 0 , nitrite - >1, nitrate - 40

aging barrel - ph - 7.6, ammo - 0, nitrite - 0, nitrate - 0

tank after w/c - ph - 7.2, ammo - 0, nitrite - .25. nitrate - <5



Jim

[pascal]

Are you sure the bio activity in your filter is still working? Metronidazole has also antibiotic action, so maybe it can affect your filterbacteria, especially since you doubled the dosis and apply it twice a day. Even if you add bacteria artificially, they can die and create supplementary waste. If your filter is working properly, there should be no reason why at once you have nitrites in your water so quickly (after 1 day). Don't consider this as the truth, I'm just thinking about possible causes together with you.
I would keep on performing waterchanges during the treatment (is only a few days I think), and then put some substrate from another healthy tank in the filter.
A one inch sand substrate is not appropriate to my opinion. I have been keeping discus for decades in planted tanks. I'm keeping them since 1,5 years with a one layer of gravel covering hardly the surface of the tank (a bare bottom tank is not so fish friendly to me). It went never as well as today. I really believe it works better without a sand or gravel bottom.

[jim LI]

pascal, thanks for replying.. i do have another tank i can take some substrate from. This tank has been running just the way it is for about a year with no issues, other then my last filter pad change. so i am at a loss as the why the cycle won't complete. i am also getting a qt tank and moving the suspected fish that are pooping white into that tank and stop medicating the display tank. i hope that the new substrate and qt tank help out the big tank.

jim

[pascal]

I didn't use metronidazole since at least 20 years or more. As no other medication in fact. I didn't need it, so my experience is rather old and not updated.

[Willie]

Any level of nitrite is an indication of incomplete biological cycling. I recommend you move a cycled filter or filter material as soon as possible.

Good luck, Willie

[jim LI]

thanks for the replies. i had to get replacement substrat for the material that I am taking out of my established tank. but a question came to mind. if there is something going on in my discus tank that is not letting the cycle to complete, will adding cycled material to the uncylced tank have a positive affect or will whatever is happening in the discus tank that is not allowing the cycle to complete have the same affect on the cycled material i just added? i hope that made sense.

thanks

[jim LI]

So, last night I was all set to move some cycled substrate to my discus tank, when I tested for nitrites before the move. the reading was 0 for nitrites and 20 for nitrates. I did 3 things on monday, changed out my filter floss from the existing filters, moved the sick fish to a qt tank and restarted my purigen reactor. the nitrite level went from over 1 to 0 over night. this is enough to drive you crazy, but the important thing is the tank is hopefully completely cycled now. thanks for all the replies and suggestions. i will be watching the nitrite level for the next few days just to be sure.