Water Test Question

orb4me · 07-14-2008, 02:16 PM

deleted by me

Jay · 07-14-2008, 05:45 PM

Well said orb4me!

While the API tests are far superior to strips, you still have to take into consideration that they are only ballpark and can be + - .5 or a little more. That degree of error is just fine when you gain some experience...IMO, just don't make any critical decisions without consulting us here.

My approach to LFS employees is usually just to smile, nod my head, get what I need and leave. I do have to honestly admit that I have met a few who are really trying.

Jay

italianguy626 · 07-15-2008, 09:41 PM

I picked up a Tetra test kit when I got my aquarium and had been using it to track my ammonia and nitrite levels. There was no nitrate test in the kit, so I picked up an API nitrate test kit.

Since I've been doing a fishless cycle, I've kept the ammonia to 5.0 mg/L. With the Tetra test kit, the nitrite test showed a spike about two weeks ago (3.3+ mg/L), and each subsequent test showed just slight reductions. I started testing for nitrates once the nitrites spiked.

Nitrites have slowly been going down and nitrates have slowly been going up. I've been between 10 and 20 mg/L nitrates for about a week.

I ran out of the Tetra nitrite test solution, and picked up an API nitrite test kit. However, it seems the API test kit isn't working.

Here is what happens - the instructions say to fill the accompanying vial with 5 ml of tank water and then add five drops of the test solution and then shake it for five seconds and then wait five minutes for color to develop.

The problem is that while I get a color change right off the bat, after about two minutes the color fades and turns a color that isn't indicated on the test comparison card.

On a side note, I also had to pick up an ammonia test kit as my original solutions ran out. Again, I bought an API. However, the API ammonia test is getting a similar result to the Tetra ammonia test.

So, I guess my question is did I get a "bad" API Nitrite test kit? Are the instructions incorrect? How could I be getting a consistent reading with the Tetra nitrite test kit and then the API nitrite test kit indicates nothing? There is nothing at API's website about any of this. Any ideas?

Jay · 07-17-2008, 06:41 AM

I have rarely seen an exact match between the vial and the color card. Usually the vial color is much less intense than the printed color. It takes a good eye for color to determine the range and even tougher if it is in-between.

Then to make it worse, the color changes on some tests are very subtle. The API Nitrate card is a good example for me I have real difficulty reading between 20 - 160 ppm, now that's an accuracy problem

I only use API to check if I am in the Ball Park or trending one way or another, and I often have to get a second opinion from my wife who has excellent color sense.

Unfortunately, for more accuracy and easier reading, you need to move up to the high end guys. For example Salifret test kits go for about $20 - 30 each kit; Lamott kits go for $30 - 70 per test kit. Personally, I have no need for that kind of accuracy.

From the results you are getting it sounds like your tank is trending towards completing the cycle process as it is getting difficult to get a fix on ammonia and nitrites. Keep in mind that the API kit is a Nessler reagent. It will give you total ammonia (both ammonia and ammonium). If you want to see just toxic ammonia you need to go to a Salicylate test kit.

Jay

orb4me · 07-18-2008, 06:08 PM

deleted by me

italianguy626 · 07-18-2008, 09:33 PM

Quote:

Originally Posted by orb4me

API nitrite test says wait 5 seconds, not minutes.

Are you getting a color that is sort of between the colors on the chart or some off the wall color? black, green?

Some men, not all, are to some degree color blind, maybe ask wife or another female to read the color?

I put the vial over the colors and the one I cant see is the correct one, but thats just me.

Just looked at the API instructions that came with my kit. It says to wait 5 minutes. In every language on the sheet. The color after five minutes was a greenish hue, which isn't on the test card.

5 seconds makes much more sense!

I'm a little bit red/green color deficient. Not enough to not be able to read the tests, though.

So far, so good. Just waiting for the dang nitrates to spike. :twiddles thumbs:

orb4me · 07-19-2008, 02:42 PM

deleted by me

Jay · 07-19-2008, 03:22 PM

Quote:

Im surprised that Tommy or Jay has not jumped all over this

LOL, common mistake

IME it has always been my habit to contact my local water authority, get a name, be really nice to them, and get them to send a fax, quote the numbers to you etc. of the water parameters you need to know coming out of the tap. NO3, PO4, GH, KH, etc. Otherwise you are flying blind at water change time using low end test kits.

Tell them the truth about your hobby and your need to know... 9 times out of 10 they will go out of their way to be helpful.

Jay

orb4me · 07-20-2008, 04:32 PM

deleted by me

Jay · 07-20-2008, 04:42 PM

Quote:

Doesnt the water change from time to time at the local water department? We get some kind a statement every so often from them telling us how the water tested, it must be once a year, I havent seen one since I cared what was in it. I just remember a lot of big words and numbers beside them.
__________________

That's exactly my point. They test much more frequently than the once a year required (feds) report.

I have a good relationship with my water guy...he faxes me (on request) updates when I think I need them.

We can do a quick seminar on ppm, ppb, etc. Let me know

Jay