well here are my test results in my 55g tank with 1 oscar and a snail. i did a 50% water change 6 days ago...

nitrate- 40-50
nitrite-0
amonia-0-0.2
ph- 7

looks like its time for another water change

i didnt think they would get that high after 6 days. im gonna take some water to the lfs and get them to test it and see if they match my results

well...my test kits seem to be crap.

i just took my water to my lfs and my results were

nitrate-0.5
nitrite-0
ph-6
amonia-0

i think i need new test kits lol...my ones are only like a month old aswell:(

Well that's pretty scary.
I usually trust my Tests for about 3-4 months, and after that I do what you did, take a sample to my reputable LFS and if they are comparable I use them for another two.
But 1 month old???
I'm not sure where you purchased it ... but I would complain.

If you did happen to purchase it from Petsmart, Petco, or types like them. You have to factor in that it may have been on the shelf for a couple of months. And maybe in the stock room a couple more.
I'm not saying that a reputable LFS is any different, but they are more than likely to stand behind their sale.

I believe that there should be a law stating any and every chemical or testing unit should have either stale date or manufacturing date.

I believe you should check with more testing, it's difficult to say which measure is correct and which is not. Hopefully the LFS reading stand.

It may not be cost-efficient, but I have multiple liquid reagent test kits (API FW Master Test Kit, TetraTest Laborett, Marine Enterprises Inc Nitrate Test...) AND also test strips (for screening Nitrates mostly). This is not something I planned for, I just ran out of certain reagents and another brand was available that particular day while the one I was looking for is only for sale at certain LFS that closed early... whatever!

Sidenote: Fishkeeping in the third world can be complicated by some unimaginable issues -Have you ever visited six different LFS to find ANY brand of water dechlorinator? In the end, maybe not at the moment I experience them, obstacles make this even more fun.

I don't do scheduled weekly readings of all parameters for all tanks anymore. Observing the tanks, doing regular maintenance... I guess fish health is the best parameter to keep an eye on once the tank is established and the whole system is stable, giving nothing goes out of path.

Proper storage and handling of test reagents, as well as its manufacturing date should be considered when unexpected results come out. False positives, but even worse, false negatives do happen. Touching the sample solution with our fingertips could tamper some results.

Pepe
Santo Domingo

actually a .5 nitrate reading after a week seeems a little low to me not to mention that my api kit doesnt measure such small increments on the nitrate scale. i would get another test kit and retest myself if i were you. the readings you are getting from your lfs just dont seem right to me.

well the guy tested with 2 different test kits and got the same result both times.. i know one of the kits was..erm...well i cant remember but it was the same kit that ofl recomends as they sell it in the shop. i will be buying it soon:).. aquarium pharmisuticls or something like that???

i also use the api kit(american pharmaceuticals inc.) and like i said the nitrate comparison card only reads in whole numbers 5,10,20,40,80,160.

a .5 reading is only available on the nitrite and ammonia cards.

perhaps it would be better if you got your own kit and did your tests yourself then you can be sure about the readings you get.

maybe it was 5. my memory aint that good lol.

i have the API master kit and have had no problems, that is the only kit i will use now. i would think your nitrates are either 5 or 50, but it wouldnt be .5.
get it retested to be safe

it was tested twice, with 2 different kits in that shop. i also tested it but my tests turned out to be dodgey.

the result must have been 5. it is a 260 liter tank with only 1 7inch oscar so they wont be high anyway..thats why when my tests came back funny i went to the shop to have them re-tested