Problem With Fishless Cycle

[scouse_andy]

I set up my 240 litre on a fishless cycle, adding about 10 millilitres of Jeyes Kleen Off (ammonia source) twice a day, which raised ammonia levels to just over 4ppm and doing regular tests.

I also had some mature media from my Biorb which I added to the filter. After about five days there were enough bacteria to get rid of the ammonia in about 9 hours. The nitrites shot up and then about ten days later they came down, not quite to zero but about 0.5.

At this point I thought that the tank was fairly close to finishing cycling so I ordered a load of plants online and put them into the tank. I put all the filter sponges into a bucket with the water from the tank for about 4 hours whilst I took most of the water out of the tank and planted away to my heart's content. I then filled the tank back up with tap water and added Stress Coat to get rid of chlorine and chloramines before putting the sponges back in and turning the filter and thermometer straight on and adding enough ammonia to take things back to 4ppm.

I anticipated finishing off the cycle for another 3/4 days maybe a week and then stocking my tank.

When I checked the water readings this morning they were off the scale. Ammonia still at 4ppm, nitrite .5 and nitrate 10. It would appear as though I've lost the vast majority of my beneficial bacteria.

I am obviously a bit disappointed as it looks as though I'll have to cycle again for another 3-4 weeks. On the plus side, at least I didn't have a tankful of fish to poison!

Can somebody please let me know if I have made a schoolboy error somewhere along the line as I need to make sure I don't make the same mistake again.

Could the bacteria have died in 4 hours because the water they were in got cold? Could adding all the plants have made this kind of a difference to the cycle.

I'm really anxious to know how to get it right next time.

When it has cycled am I best to float the sponges on the surface of the tank whilst I do my big water change to remove the nitrates rather than putting them in a bucket?

Thanks in advance for any help.

 

[Frost]

Hello scouse_andy. The very same thing happened to me directly after the water change in my fishless cycle. Unfortunately for me though i bought fish just after changing the water ( i didnt test it - just figured the bacteria wouldnt die in that short amount of time).

I wouldnt get too worried, there should still be some bacteria on your filter media, it took mine 2/3 days to go back to usual, that was with the fish in the tank.

Sorry I can't add much more, i'm not very wise on these things.

Good luck to you.

 

[jesseoneill]

Could the bacteria have died in 4 hours because the water they were in got cold?

Almost correct. Putting the sponges in still water didn't kill the bacteria because of cold water, but it was (IMO) the contributing factor. The bacteria on filter media need to be kept in moving water in order to get a constant supply of nutrients. If the bacteria are in still water they will quickly (approximately 1 hour) use up the oxygen/ammonia/whatever around them and starve to death. For this reason it's best to keep your filter running (even with the flow turned down) while you are doing a water change. I'm not experienced with all kinds of filters, but I can't think of a standard filter where you have to turn it off and/or remove the media while doing a water change.

If for some reason you absolutely have to turn off your filter (like I did when I recently changed my substrate), it's better to take the filter off and run it in whatever bucket/pail/etc that you have the old tank water in. If that isn't possible, then at the very least pour some tank water through the media every 15 minutes or so.

 

[rdd1952]

Could the bacteria have died in 4 hours because the water they were in got cold?

Almost correct. Putting the sponges in still water didn't kill the bacteria because of cold water, but it was (IMO) the contributing factor. The bacteria on filter media need to be kept in moving water in order to get a constant supply of nutrients. If the bacteria are in still water they will quickly (approximately 1 hour) use up the oxygen/ammonia/whatever around them and starve to death. For this reason it's best to keep your filter running (even with the flow turned down) while you are doing a water change. I'm not experienced with all kinds of filters, but I can't think of a standard filter where you have to turn it off and/or remove the media while doing a water change.

If for some reason you absolutely have to turn off your filter (like I did when I recently changed my substrate), it's better to take the filter off and run it in whatever bucket/pail/etc that you have the old tank water in. If that isn't possible, then at the very least pour some tank water through the media every 15 minutes or so.

It should take quite a bit longer than that. I have accidentally left my filters unplugged after a water change for 10 to 12 hours with absolutely no ill effects. And any time I do a water change, the first tank I do always has the filter off for over an hour. I use a python so I remove water and gravel vac all tanks before I begin filling them back up. There will probably be some die-off after an hour but definitely not enough to really matter.

When the nitrite drops the first time, the tank still has a way to go to be fully cycled. It's close but not quite there. Since you used seed media, maybe it was a little quicker. I don't think any tank is fully cyclled until 4 ppm of ammonia are completely gone in 10-12 hours, no ammonia and no nitrite.

 

[scouse_andy]

I realised that the tank still had some way to go til it was full cycled as the nitrite wasn't quite at zero and I was planning on finishing the cycle off with the plants in but whatever happened obviously set me back quite a long way.

I will make sure that when I do my 75-90 percent water change I float the sponges and get the water out and back in again, dechlorinated, as quickly as possible.

It won't be a problem for routine maintenance as a 25 percent ish water change can be done reasonably quickly. I didn't realise about keeping the flow of water going.

Do others agree that still water was probably the reason?

 

[rdd1952]

You shouldn't have to worry about the big water change either. When I do them, I simply unplug the filter and heater, syphon out the water, do what cleaning I need to do and refill. I don't do anything different with the filter sponges or media. The bacteria should easily be good for 8 to 10 hours without any significant lose.

And I DO NOT agree the still water was the problem, not for just 4 hours.

 

[steve_m]

Add an air stone to your bucket of media. Water flow and oxygen are more vital then the water temp over a 4 hr period. Also test the ammonia levels before dropping your media back in.

 

[scouse_andy]

thanks for the advice about the airstone.

Just to clarify do you mean test the water stats in the tank which I've refilled with dechlorinated tap water before putting the sponges back in?

 

[doresy]

I am no expert on starting a tank using ammonia (was a long time ago!) but what I have read in these forums when using ammonia it needs to be pure ammonia so looking at the op it say quote; Jeyes Kleen Off (ammonia source) which sounds to me to be a cleaning agent. Have you checked the ingredients also, shake it...if it froths it's no good for this.


Just a thought

 

[rdd1952]

Jeyes Kleen Off is one mentioned in this as being an acceptible one.

 

[steve_m]

jeyes Kleen off is perfect its made from water and amonia. i always test the fresh water im putting in the tank to make sure its low on nitrates (<40ppm)and all of the clorine has been removed.