Confused with fishless cycle

[reefrunner69]

S I've been cycling this tank since the end of April http://www.aquariumadvice.com/forums/f14/tank-wont-complete-cycle-217154.html that thread depicts the issues I have had. I started over cycling with a raw shrimp and then straight ammonia. I have been dosing the tank to 4ppm each night and it seems to have started coming down, I can does it to 4ppm now and within 24 hours it goes to .5. So 2 nights ago I dosed it to 2ppm expecting it to be 0 within 24 hours, no dice. It was actually somewhere between 1ppm and .5 ppm, so I didn't dose at all last night, today (approx 16 hours after the last test) it was .5ppm. So I am wondering why the bacteria can convert 3.5ppm ammonia in 24 hours but can't convert 2ppm in 24 hours and so on. I have never done a fishless cycle before, early on in the hobby was fish in and since then I have always cycled with uncurred (fresh) live rock.

It's all the more confusing because there are snails a cleaner shrimp and several hermits all doing swimmingly in the tank and in the last week I have seen an explosion of micro fauna in the tank.

I dosed it back to 4 ppm and I'm going to test again this evening and see how low and quickly the bacteria converts it.

 

[Ingy]

Are your nitrite levels dropping to 0 overnight with the dosing ? API are known to give false ammonia readings. If nitrite is hitting 0 I'd take a sample to your LFS for an ammonia measurement. You may be complete already.

 

[reefrunner69]

I do use API but I verified with aquarium systems test. Nitrite stays at 1ppm while nitrates go up.

 

[reefrunner69]

So, as I said, I dosed the tank to 4ppm this afternoon (I tested and verified it was 4ppm ammonia) and just tested it and it is between 1 and 2 ppm. So it has converted about 2.5 ppm ammonia in just a few hours. I'll test again tomorrow afternoon and I expect it to be 0, but if it holds true to form...it will be .5ppm.

 

[reefrunner69]

Ammonia is .5ppm tonight. I won't dose tonight and see if it goes to 0 by tomorrow, I'm betting it doesn't.

 

[bigben2057]

Id stop dosing ammonia your tank is most likely ready and cycled. Its been almost 3 mo. if I read correctly.

 

[reefrunner69]

Yeah, it has. I won't dose and we'll see what happens, hopefully it will be good to go soon.

 

[Ingy]

What are your trAte levels at by now. excessive nitrates can cause the cycle to stall. But they'd have to be pretty high

 

[reefrunner69]

What are your trAte levels at by now. excessive nitrates can cause the cycle to stall. But they'd have to be pretty high

How excessive? They are > 100 exactly how high I am unsure, that's as high as the aquarium systems test goes.

 

[Sniperhank]

After 3 months I can't see the cycle not beingdone. Do a water change, check levels, and if all well add a fish.

 

[Ingy]

Agree..

 

[reefrunner69]

Ammonia still .5, nitrites still 1ppm and ph is 7.8-8.0

 

[reefrunner69]

After 3 months I can't see the cycle not beingdone. Do a water change, check levels, and if all well add a fish.

I have done 3 10 gallon water changes over the last three days (20 gallon tank). Ammonia is still at .5ppm, nitrite has gone down to .5 and nitrates are now about 180ppm which means after 3 50% water changes they started at 1440ppm. That's a lot of nitrate.

My plan is to continue the water changes daily (today I'm going to attempt to clean the sand bed in the hob refugium and remove the rocks and vacuum under and behind) until the nitrates are very low.

Any thoughts?

 

[Sniperhank]

Are you using tap water?

 

[reefrunner69]

Are you using tap water?

Nope, I use RO/DI water. I started the tank with distilled, then go a week or two I used the water from the culigan station at Walmart, and after doing the math, bought a new RO/DI with booster pump.

 

[Sniperhank]

And we've tested the culigan station water?

 

[reefrunner69]

And we've tested the culigan station water?

When I used it I did, TDS was about 7ppm, the freshwater tested 0 for ammonia, after mixing to 35ppt it tested ammonia 2ppm, nitrite 0, nitrate 0 and ph 8.4 (red sea coral pro salt).

 

[reefrunner69]

Here is another curious fact, I have always run my actinics during the cycle, and while I have expected a hair algae outbreak, I have seen a couple of days worth of diatoms, and new coralline algae growth. I have one rock that had 0 coralline algae on it and now there are several spots of pink/purple coralline growth.

 

[Sniperhank]

Well, I'd say you're cycled and just have a bad test kit at this point. Ammonia readings through all of this doesn't make sense?

 

[reefrunner69]

Well, I'd say you're cycled and just have a bad test kit at this point. Ammonia readings through all of this doesn't make sense?

I would agree, if it weren't for another test kit that agrees with it. I test with API for easy of use and time, but I also have an aquarium systems (instant ocean) master test kit as well, and they agree with each other. That's not to say both aren't faulty, but its unlikely. I am going to the LFS tomorrow and I'll take a water sample and see how it goes.