Fishless Cycle Question.

[joshv155]

Question: I think I dosed my tank up to 2-3ppm yesterday around 3pm. At about 4pm today I tested it and my ammonia was 0 and nitrites were 1ppm. Tested at 8pm and nitrites were .25 ppm. So it's obviously going down. Is my cycle complete and it's taking longer to convert because I dosed the ammonia to high ? Or is my cycle not done yet until it coverts all the ammonia to nitrate in 24 hours ? I have a little plastic deal I use to dose the ammonia and just filled it up to what I thought was 1/2 way to get 2ppm instead of 4ppm but I didn't measure it out to make sure it was exactly 1/2...

 

[jlk]

Its not quite done if its not converting the amm>nitrate within 24hrs, but your just about there! If you dosed a little bit more amm than usual, that may be why you didnt see the complete conversion. I would just give things a few more days to be sure everything is working correctly.

 

[joshv155]

*sigh* So it looks like my cycle is yet to be done. The nitrites are going down but not fast enough to be converted in 24 hours. I am wondering if the time the nitrites were down to 0 was because of the large PWC.

My nitrites were at 5.0 ppm that past 2 days .....so not done yet.....they did go down from 2.0 ppm to .25 ppm the other day over about 8 hours...but back up to 5.0 ppm after dosing the tank to 2.0 ppm ammonia.

So does 2.0 ammonia turn into 2.0 nitrites ? Just wondering how the conversion works.

 

[jlk]

*sigh* So it looks like my cycle is yet to be done. The nitrites are going down but not fast enough to be converted in 24 hours. I am wondering if the time the nitrites were down to 0 was because of the large PWC.

My nitrites were at 5.0 ppm that past 2 days .....so not done yet.....they did go down from 2.0 ppm to .25 ppm the other day over about 8 hours...but back up to 5.0 ppm after dosing the tank to 2.0 ppm ammonia.

So does 2.0 ammonia turn into 2.0 nitrites ? Just wondering how the conversion works.

This is a great question and I asked the same thing the first time I tried a fishless cycle. I never received an exact answer nor have I been able to find the exact answer. I am honestly not sure what the exact conversion rate is (ie- 1ppm amm > xppm nitrite > yppm nitrate). Amm seems to convert to a slightly higher amount of nitrite & nitrite converts to an exponential amount of nitrate. Ill do some more looking & see if I can find a more information.

 

[corinne118s]

Ok here's the basic chemistry:

You have ammonia (NH3) from waste, etc. Ammonia mixes with water to create ammonium (NH4+) by stealing hydrogen (H) and leaving oxygen (O2) molecules.

Ammonium and oxygen recombine to form nitrites, hydrogen gas, and water molecules.

2NH4 + 3O2 -> 2NO2 + 4H + 2H2O

Therefore in theory, the ratio is 1:1. However, no water is perfect so numbers will be off but you can generally assume they will equally convert.

(someone correct if I am wrong)

The process can take a while because the process requires energy to break equal polarities of NH3 and H2O

 

[corinne118s]

Might seem exponential because..

Say you have 1ppm ammonia and 1ppm nitrite and 0ppm nitrate in your last test. A day later you read 0ppm for both ammonia and nitrite. Your nitrate should be 2ppm because both completed the cycle. Make sense?

 

[joshv155]

Ya it makes sense. I just had my wife test the water cause I am at work and its was right about 24 hours...give or take 30 mins. The previous day my tests were:

Ammonia: 3ppm
Nitrates: 5.0 + ppm
Didn't test nitrates

Today test was:

Ammonia: .25 ppm
nitrites:.25 ppm

Going to test it tonight when I get home. If its at 0 for both going to do a 90 % PWC (my python arrived today) and see for the next couple days the readings.

I was dosing the ammonia when the nitrites were at .25 to 1ppm the last couple days cause the ammonia was at 0 and it was obvious the nitrites were coming down....but it made it so I didn't have an accurate time table as to how long it took to go from ammonia>nitrites>nitrates....I think i am making this harder on myself that it needs to be.

 

[HeatherW]

Ya it makes sense. I just had my wife test the water cause I am at work and its was right about 24 hours...give or take 30 mins. The previous day my tests were:

Ammonia: 3ppm
Nitrates: 5.0 + ppm
Didn't test nitrates

Today test was:

Ammonia: .25 ppm
nitrites:.25 ppm

Going to test it tonight when I get home. If its at 0 for both going to do a 90 % PWC (my python arrived today) and see for the next couple days the readings.

I was dosing the ammonia when the nitrites were at .25 to 1ppm the last couple days cause the ammonia was at 0 and it was obvious the nitrites were coming down....but it made it so I didn't have an accurate time table as to how long it took to go from ammonia>nitrites>nitrates....I think i am making this harder on myself that it needs to be.

OK, not trying to confuse anyone here... I am doing my first fishless cycle right now too and trying to get a handle on how this all works.
so here is my question: why are you doing a water change tonight?? shouldn't you just redose the ammonia up to 2ppm or whatever and let it keep doing its thing? I thought you only did the water change when the nitrites were off the charts or when you were done and were getting rid of the nitrAtes?

 

[joshv155]

I really want to know if how long it's taking me to convert everything to nitrates. I guess I don't have to do a PWC...I'm new at this too so maybe I'm not supposed 2. I guess I could wait to male sure it's converting to nitrates on 24 hours then do the PWC before I add fish.

 

[jlk]

I really want to know if how long it's taking me to convert everything to nitrates. I guess I don't have to do a PWC...I'm new at this too so maybe I'm not supposed 2. I guess I could wait to male sure it's converting to nitrates on 24 hours then do the PWC before I add fish.

The water change is up to you. If you want to zero everything out completely to see how fast things are being converted or the amount of nitrates you exactly wind up with from x amount of ammonia, go ahead with the water change. Its not necessary though unless theres an issue with your ph. I would just keep dosing & see if everything is being converted after 24hrs. If so, a water change to bring down nitrates & you will be ready for fish!

 

[corinne118s]

You are almost done I'd give it another week to be sure. Dose one or two more times wait for everything to zero, do PWC (90%) to bring down nitrates and you should be golden. Even if you starting stocking now you would be ok but it's better to wait until everything is perfect.

 

[corinne118s]

OK, not trying to confuse anyone here... I am doing my first fishless cycle right now too and trying to get a handle on how this all works.
so here is my question: why are you doing a water change tonight?? shouldn't you just redose the ammonia up to 2ppm or whatever and let it keep doing its thing? I thought you only did the water change when the nitrites were off the charts or when you were done and were getting rid of the nitrAtes?

Don't worry if you PWC it doesn't hurt anything it's just not necessary

 

[joshv155]

Ok - so 2 days where my tank has converted everything in 24 hours ! I'm good to go. Currently using my python to drain the tank...man that thing is awesome!

Question: Can I add the water from the tank straight back into the tank THEN add prime to it since there are no fish ? Or will the chlorine kill off the good bacteria ? I really don't want to keep lugging 5 gallon jugs of water just to add prime in each one...but if that is the correct way I will. Thanks...

 

[Hholly]

Always add Prime first to the tank.

 

[joshv155]

Can I add it to the water I left in the tank then pump the water back in with my python straight from the tap ?

 

[jlk]

You can run water straight from your tap into your tank as long as you dose prime first. Give the Prime @10mins to disperse through the tank & then turn everything back on.

 

[jlk]

Ok - so 2 days where my tank has converted everything in 24 hours ! I'm good to go. Currently using my python to drain the tank...man that thing is awesome!

Question: Can I add the water from the tank straight back into the tank THEN add prime to it since there are no fish ? Or will the chlorine kill off the good bacteria ? I really don't want to keep lugging 5 gallon jugs of water just to add prime in each one...but if that is the correct way I will. Thanks...

Congrats on being cycled!!

 

[joshv155]

You can run water straight from your tap into your tank as long as you dose prime first. Give the Prime @10mins to disperse through the tank & then turn everything back on.

Sorry, just want to clarify. Dose prime into tank water that I left (not much cause I took about 85 - 90% out) then wait 10 mins and add water back in ?

 

[joshv155]

Congrats on being cycled!!

Thanks for all the help !

 

[jlk]

Sorry, just want to clarify. Dose prime into tank water that I left (not much cause I took about 85 - 90% out) then wait 10 mins and add water back in ?

Sorry for the confusion! Dose your Prime for the size of the tank, add your water, & wait @10+ mins for the Prime to disperse throughout your water before turning your filters back on.