GardenBanter.co.uk - View Single Post

24-05-2005, 11:06 PM

wrote:
Most Nitrate kits that I have come across are similar and some are prone to
requiring too much operator interpretation which tends to make them worse
than useless unless you only require a guide number. I have not had good
experiences with the quick-dip testers, their accuracy is not very
consistent for nitrates (and IMHO are suspect generally).

If you just want a quick "am I in a safe zone" check, then the dip strips
will serve this purpose. If you want "how many ppm do I have", then that's
where the dip strips are suspect. I've found them great as a "presence of"
indicator but very poor as a "how much" measurement. I have gotten good
with the Jungle 5-in-1 dip strips at interpretting its shades of pink as
under 10ppm (safe), 10-20ppm (my tap water levels, ugg) and 20-40ppm (my
cichlid tank thanks to the high tap water levels), but nothing more
definative than that. And those judgements were made not off its color
scale printed on the label but by comparing it to liquid kit results. Most
of the dry tab and liquid test kits do require shaking and waiting, but
it's the only way to get a good reading on exactly how many ppm you have.
As for the differing results, read the documentation. Some have different
ways of expressing their scales.