Fishless Nitrogen Cycle

[boyen]

Hi Guys,

I'm new to the aquarium world and have a few questions regarding a fishless nitrogen cycle.

I have added ammonium over the last couple of weeks ensuring the level never got above 4 ppm. Now I see high levels of nitrite, 5 ppm, as well as very high levels of nitrate (60-80 ppm). Is this normal?

I have done a 50-60% water change but the nitrite is still there as well as the nitrate. Should I hold back on ammonium?

I have several snails in there and they seem to be doing fine. I had 8-10 plants in the aquarium but they all died except for one while I was on a business trip and my wife was in charge . Could it be the gravel that has absorbed a lot of nitrite and nitrate and hence the levels are not dropping after a water change?

Any suggestions are highly appreciated.

Regards,
Lars

 

[sinibotia]

Likely you just have really high levels of both. Try doing two consecutive water changes of 80-90%. Then test your water.

I personally think that your tank has enough bacteria to add fish. After those water changes, test your water. If you're at 0 for everything then dose 2ppm ammonia. Finally, test your water again same time tomorrow. If your water reads 0 for ammonia and nitrite and has a Nitrate reading then just do another big water change and add your fish!

 

[boyen]

Thanks for the quick reply, sinibotia! Much appreciated!

I did the following:

1. Did a 90% water change
2. Let my canister filter run for 15 minutes
3. Did another 90% water change
4. Let the filter run another 15 minuter before measurements

The result of my measurements after the changes:

NH4: 0.05-0.1ppm
NO3: 5ppm
NO2: 0.7ppm

What I don't like is the NO2 still being rather high after such a change. Any suggestions?

Once again thanks for any input!

 

[sinibotia]

All that means is that your bacteria are processing a TON of ammonia. I can almost guarantee that if you check again tomorrow your numbers will be 0/0/10 or so. Which means you're basically ready for fish!

 

[boyen]

****, you are fast. Thanks

Should I add any ammonium or just leave it till tomorrow and test again to see if you were right in the 0/0/10 prediction?

 

[sinibotia]

****, you are fast. Thanks

Should I add any ammonium or just leave it till tomorrow and test again to see if you were right in the 0/0/10 prediction?

"Lazy" saturday, I'm home with the toddler and the fish

I would wait till tomorrow. Honestly if it were my tank I'd be convinced it was cycled. If you want to be extra sure, if it's 0/0/10 tomorrow then just dose to 2ppm ammonia and wait 24 hours.

Should process all the ammonia to nitrate in that time, then do a big water change and get some fish! Gosh I hate empty fishless cycling tanks!

 

[boyen]

Thanks!

Will test tomorrow. And I agree fishless tanks are not very nice

The tank is for my 8 year old daughter. She has been asking me for the last 3 weeks if we can put in some fish - every single day She'll be a happy girl tomorrow when I tell her.

Thanks and enjoy the rest of your evening!

 

[sinibotia]

The tank is for my 8 year old daughter.

Be careful what you're starting! I got my first tank when I was 9. That was 12 years, 400 gallons worth of tanks and half an aquaculture degree ago

 

[boyen]

She is curious and so willing to learn. It'd an expensive hobby. But as long as she likes it it's worth every cent.

 

[boyen]

Did a test of the water today.

NH4: <0.05ppm
NO2: 1.0ppm
NO3: 15ppm
PH: 7.7

Something is not quite right. Should I add more ammonium? I also have a bottle of Tetra SafeStart. Should I try and add this? I have a feeling I still miss the the bacteria converting nitrite to nitrate.

Thanks for any feedback!

 

[sinibotia]

If you didn't have the nitrite bacteria you wouldn't see Nitrate. Only difference between what I was expecting and what showed up is the 1ppm nitrite. IMO you're all set so proceed with the big water change and you can add fish, or if you want to be extra sure then proceed with the 2ppm ammonia dose.

 

[boyen]

Thanks!

I did a 90% water change again. No NH4, NO2 and ca. 5ppm NO3. Have added 2ppm ammonia and will test tomorrow. If everything is fine then the fish are coming - finally

 

[boyen]

Tested the water 24h after adding 2ppm ammonia. Result

NH4: 0.6
NO2: above 1ppm
NO3: 80ppm

I feel like something is not quite right yet. Am I being too cautious?

Thanks.

 

[sinibotia]

Your NO3 skyrocketed so your tank is definitely cycled and it seems like there's some kind of ammonia source in the tank? I would do another big water change and then test again tomorrow.

 

[boyen]

Thanks.

Will have to wait till tomorrow. Ran out of water conditioner

I have 10-15 snails in there. I did add some Tetra SafeStart I had left. Could that be the cause for the high NO3?

 

[sinibotia]

Yeah that was probably it!

 

[boyen]

Thanks Sinibotia. Aquarium is up and running with fish. All values look great.

Lars