high nitrates

[ineke]

does anyone know if when getting right to the bottom of a test bottle does the fluid get more concentrated? I am getting 2 different readings one from a new test kit and a higher reading from an almost empty bottle. Both have the same expiry date but the old one I have been using since january- was new then.

[BlueBolts]

With the nitrates test kit (presuming APi), it depends whether you really shake them around (30 sec for Bottle #2)..... if you don't, then the last few test would perhaps be more concentrated. Always go for the one showing the higher level....just to be on the safe side

[ineke]

Thanks BB I am setting up a new tank a and although the only change is the substrate and about 1/4 of the water I had a very high nitrate reading 24 hours later so having a new test kit( API) I used that to double check and it registered much lower. I ended redoing it with both and really shaking the bottles for the full minute as required and although they were closer the old test kit showed a higher reading again. So checked a second tank with pretty much the same results one higher than the other so guessed it had to be the concentration in the older bottle. I do shake the bottle each time but probably not as long as I should so lesson learnt. I did a partial water change to be on the safe side as there were no shrimp in the tank and will retest tomorrow before putting any shrimp in there:encouragement:

[BlueBolts]

Sounds perfect .... good luck with tomorrow ! :-)

[ineke]

Thanks BB changing all my tanks around now most of the reds are gone and all except the Crystal tank have been taken down and redone before new inhabitants going in. Hopefully all shrimp will be happy:)