Nitrite still too high?

[Maurice2]

I'm a bit confused with my test results, the figures seem too high. I've read that I should have:
NH4 <0.2 ppm
NO2 <0.2 ppm
NO3 <0.3 ppm
PO4 <=0.07 ppm
but the JBL test kits I have ranges that are much higher. For example the NO3 test steps are 0, 1, 2, 5, 10, and so on, so measuring to a tenth of a ppm isn't possible. Could it be that I've misunderstood scale/units/range?

Here's what I'm getting:
27°C
SG 1.022
Ph 8.2
NH4 0 ppm (but the next higher reading is 1.0 so it's hard to judge)
NO2 0.5 ppm
NO3 1 ppm
PO4 1 ppm
Ca 400 ppm

It's a 480L FOWLR, 25Kg of live rock cycled in January (NH4 dropped to 0 on 14 January). Population added during last week (all juveniles)
Royal dottback
Yellow Longnose Butterfly
Emperor Angel
False Percula
3 Yellowtail Blue Damsels
Sixline Wrasse (disappeared over the weekend; eaten?)
Spotted Mandarin (disappeared over the weekend; eaten?)
Pallette Surgeon
Small starfish
Pacifica scarlet cleaner shrimp
Banded coral shrimp
Blueleg hermit (moulted Friday, unseen since)
Fire shrimp (disappeared/hiding)

All survivors have healthy appetites, 1 feed per day.

Any comments on NO2/NO3/PO4 levels would be appreciated

 

[BillyZ]

if you added all of those fish within a week, you've most likely started a new cycle as that steep of a climb in the ammonia production in your tank will take a while before your bacteria population can catch up.

To answer the question in your subject line, any nitrIte is too high. You're best bet now would be a water change and a keeping a close eye on those levels to be sure they don't spike too high.

Double check the directions on your test kits, some offer a "low level test" option. I use salifert test kits and I can read through the top at normal values, or read through the side and divide the results by 10 for readings of <1

 

[Brenden]

Tank levels should be NH3-0, NO2-0, NO3 <20 (preferably 0) You need to add fish MUCH slower to your tank and make better choices. For example the mandarin would have died of starvation anyways. As Billy said you are probably going to start a second cycle with all the additions you made.

 

[Maurice2]

Thank you for the quick reply

As the LFS suggested, I've been keeping an eye on NH4 every day or two and it's never moved above zero. If the NH4 is 0 then there's nothing to convert into NO2, and thence into NO3 or have I misunderstood the chemical process?

Thanks again

 

[Brenden]

You can have a reading of 0 on NH3 and still have NO2. True you can not have NO2 without first having NH3 but the amount of bacteria available for each will very so you should still watch levels and have water mixed in the event you need a WC.

 

[DragonForce]

I don't mean to bash the idea of 0 nitrates and I understand why the cause problems but many of my corals seem to look better with 5-10ppm nitrates. I just thought this was an interesting topic to think about.

 

[BillyZ]

... or have I misunderstood the chemical process?

You might have a slight missunderstanding. Any aquarium with life in it has ammonia. A reading of 0 ammonia simply means that the population of bacteria that processes the ammonia is large enough to handle it before it becomes a measurable level.

That bacteria feeds on portions of the ammonia and what is left over is nitrites. There is also bacteria, different from the first, that processes the nitrites and leaves nitrates behind.

There is then a third form of bacteria that can use the oxygen in the nitrates to survive in areas of extremely low oxygen. Deep sand beds and dense LR are the only places this can occur and thus why nitrates are the last to go and the "hardest" for us to maintain with a natural process.

so to sum up a very basic line of events, Fish > ammonia > nitrite > nitrate > (disolved gases that escape your tank at the surface)

All those elements are always present in your system. Readings greater than 0 simply mean that portion of the nitrogen cycle is out of balance and needs time to adjust. (Thus why you should add fish slowly )

 

[Maurice2]

Thank you all for taking the time to discuss; this is visibly a *good* place to learn 8O

Yes, my LFS boss told me off for adding a second batch of fishes too quickly, he was away and I dealt with his assistant, he said he would never have sold me them so soon. Problem was, my son promised me the pomacanthus back in October and we got carried away...

Brendan, you're spot on. The LFS said that a little (dead) mandarin would get eaten inside 24 hours, which probably accounts for why I didn't see any remains.

I guess a 25% water change on Saturday won't do any harm?

I haven't tested my tap water but the local company publishes average NO3 at 3.69, they don't publish nitrites, I'll have to ask. Seeing as I have 1ppm, can I conclude that my aquarium is getting rid of at least some of the nitrates?

Obviously some kind of water purifier would be ideal, but is it a must-have or can I survive with this tap water?

Sorry for all the questions