Difference in testing methods

My tank has been up for about a month and I started with 125 lbs of cured LR. My ammonia and nitrites has always been 0, and my nitrates have been high like in the 160 ppm area on a API drop test.

When I got the Nitrates down to 40ppm I bought 3 damsels for my 125gallon tank. According to my API tester my ammonia and nitrites have remained 0 and after a water change 4 days ago my Nitrates are at 5ppm.

My concern is that I bought some test strips and they are reading ammonia 0 nitrites 2 and my nitrates at 100. So to say the least I am lost and confused, I retested with the API tester and it still says 0,0,5 respectively.

Which test should I use or believe?

 

never trust a test strip, the API drip test is better, IMO. I'd take a water sample to your LFS and have them double check your numbers to make sure your test kit is good. Thats alot of swings

 

The problem with that is that the Lfs uses the same strip test that I bought. They are the only place within about 50 miles that I can go to.

What makes me feel a little better is actually watching the nitrates come down on the API over the last month from 160 to 5 makes me think it is some what working.

 

I'd ask, they prob have a better test kit they use for themselves, and use the strips for customers. Offer to pay them, it'll be worth your piece of mind

 

True
..also...do you have any reef people near by? friends, club etc.
..in my humble opinion, all of these "hobby" grade test kits are just ball park at best..they will keep you safe..any crazy swings you encounter , either way, any brand, needs to be followed up with "other" test or known good samples as a comparison...and fyi, I have never had ANY consistent readings with the strips...just say'n.
It sounds like your API is realistic....good post.

 

I read an article awhile back.about testing methods. It had more.to do with the actuall practice of testing rather than the type of test. There were some things tbat i.wasnt doing such as rinsing your test tubes ( i wouldnt trust the strips ) with the water you are testing and to fill up the tubes using a syringe. Those little 5ml indicator lines are not accurate from tube to tube. And i did find that a couple of my test tubes were off. So now i use a syringe to fill the 5ml regardless of where the line is. Also test at the same time of day all the time. I cant remember exactly why but it makes sense. You mentioned yoir lfs uses the same test strips. Just for an experiment the next time you go there test your water with the strips and then have them test a sample with theirs. My bet would be the results differ. Which would jusr show you how reliable those.strips.are.