Have I Cycled

[TW]

I have an ADA ammazonia substrate in the new tank, set up 21.07.08. The filters had been cycling for months on an established tank, prior to the day the tank was filled. The tank itself was set up as a terrarium for 2 months, which according to a method promoted by Tom Barr (a planted tank guru from US) where it is meant to build up the good bacteria on the tank substrate, glass, plants etc during the waterless period, thus be fully cycled by the time filled.

I filled the tank & tested for ammonia & found it present, so presumed I had killed the good bacteria while the filters were off for a a period of time while I was setting up my UV's.

Initially I added 3 prawns, then another 2 prawns.

After a few days, the tank was smelling really bad, plus I remembered that ADA soil leaches heaps of ammonia all by itself, so I removed the prawns on day 3 (maybe 4 - not sure exactly).

Ammonia reached 0 today, for the 1st time (Day 10).

Yesterday (Day 9) was the 1st day I tested for Nitrite & it was 1.0ppm (or less). Today, it is 0ppm. There's not the slightest trace of pink in the test water.

I now wish I'd tested for nitrite earlier, but had not expected the nitrite to start showing up until my ammonia started dropping. I expected a much higher spike in nitrite (eg 5ppm) before the tank cycled.

Below are my test results, up to & including today.

Day 1: 21.07.08 Ammonia: 0.25
Day 2: 22.07.08 Ammonia: 1.00
Day 3: 23.07.08 Ammonia: 2.00
Day 4: 24.07.08 Ammonia: 2.00
Day 5: 25.07.08 Ammonia: 2.00
Day 9: 29.07.08 Ammonia: 0.25ppm Nitrite: 1.0ppm
Day 10: 30.07.08 Ammonia: 0.00ppm Nitrite: 0.0ppm

I'm wondering if something has gone wrong & that my cycle somehow stalled & failed - or is it possible it has cycled & I missed the nitrite spike by not testing for it early enough.

I'm going to rush down & buy one prawn now, while shop's still open & dump that in the tank.

But wondering what the experts here think?

Thanks, Robyn.

[ChrisEddy85]

I'm no expert by a long way, but could it be possible that the Ammonia results you were noticing were already present in the substrate, and the readings are simply showing the Ammonia being leached into the water over time and then being converted into Nitrite and then Nitrate in a short period of time, as the tank was cycling correctly and well established due to the use of established filters etc?

Have you got a reading for Nitrates?

[TW]

Hi ChrisEddy85

Thanks for quick reply

I tried to reply last night, but my pc and this site were having issues & the site kept crashing when I tried to post.

I realised I missed telling you what tests were for day 6, 7 & 8. Those results are now included below.

Day 1: 21.07.08 Ammonia: 0.25ppm
Day 2: 22.07.08 Ammonia: 1.00ppm
Day 3: 23.07.08 Ammonia: 2.00ppm
Day 4: 24.07.08 Ammonia: 2.00ppm
Day 5: 25.07.08 Ammonia: 2.00ppm
Day 6: 26.07.08 Ammonia: 2.00ppm
Day 7: 27.07.08 Ammonia: 1.00ppm
Day 8: 28.07.08 Ammonia: 0.25ppm
Day 9: 29.07.08 Ammonia: 0.25ppm Nitrite: 1.0ppm
Day 10: 30.07.08 Ammonia: 0.00ppm Nitrite: 0.0ppm

Nitrate tested last night somewhere between 5ppm - 10ppm, but that doesn't mean too much, as my tap water tests at the exact same level.

I came to the decision that it has cycled, so I added the first fish. Not many, just 2 harleys, 2 cardinals & 1 discus.

Thanks for your help.

[ChrisEddy85]

Yeah, sounds like its fully cycled. The Nitrate readings are alright as well, and provided you don't register any more Ammonia or Nitrite readings, it should be good to go.

I think the site was down last night, couldn't access it nor any of the other sites affiliated with it.

Gave me a good chance to look around at different strains... hehe.

[Hollowman]

TW, Adding just one discus imo is wrong. It will get stressed on it's own, but you also need to think that adding lots of fish might lead to an ammonia spike, in a newly cycled tank.

[TW]

Yes, I was worried about both those things - that 1 was not enough (for the discus) but would 2 be too much (for a new tank).

I'll add another noe today. Thanks for your advice.

[Hollowman]

Rule of thumb says that that 4-6 fish is a nice small group. If you add more to the new system, just make sure you monitor the ammonia level closely to check for any spikes. Bit of a 'have to' trade off really.

:)

[TW]

Oh, so you think I am safe to add more in one hit. I'm talking about discus I already have had for a long time (I'm upgrading their home).

I had been used to adding a small school of fish at a time with my last new tank - but they weren't discus. I was looking at the size of a discus & thinking that one = sooo much more than say 6 rasboras. That's why I was doing one at a time.

In total, I have another 6 to transfer across. What do you think?

[norto]

TW,
You could put an established filter in their if you have a spare one and that may give you piece of mind until the fish have settled in and you are happy enough to take it out.
Regards,
Norto.

[TW]

Thanks Norto, the 2 filters were running on another tank for months. In fact, one of them was running since last Sept

[bartek]

Sorry about the late post but the high ammonia readings would have been because of your ADA substate.

Like you said ADA leaches a lot of nutrient when it first is added to a tank so the addition of prawns was probably not needed. I have had a tank take 4 weeks to cycle with ADA in it.

As some already have said, add you fish slowly and test the water before you add more. Usually 3-4 fish once a week is a good rule of thumb although this obviously depends on the size of the fish.

[TW]

Thanks bartek

I think it was the ammonia leaching from the ADA that initially messed around my tests & delayed fish entry. I'd expected the tank to be cycled straight away, what with the transfer of the 2 fully cycled filters & the bacteria that formed on the tank interior during it's 2 months as a terrarium. (There is a thread by Tom Barr in another forum, which says if a tank spends it's 1st 2 months as a terrarium, then start up with water will be fully cycled & with less algae issues).

With the addition of water, the ammonia from ADA leached into the water column. Forgetting that ADA did that, I thought I'd killed off my good filter bacteria, whilst one was off while installing the UV & later with a pump issue. Now I have rethought the whole thing.

I think now it was just that it took my two cycled filters, that had been previously used a light bio load, 10 days to increase it's good bacteria sufficiently enough to deal with the ammonia from ADA.

I'll never know for sure exactly what happened, but that's my theory.