Re: All your tank cycling questions answered here
by
DrTim's » Thu Jun 14, 2012 9:16 pm
Ok, let's see if I can clear things up - please see below
I did a partial water change using NovAqua Plus as a dechlorinator to get my nitrites down to approximately 3.0 ppm. They have held there at that reading like a rock for the last 8 days, measured twice per day.
these products do not get rid of nitrite so you are fooling yourself about that by I digress
Through contact via your website I was told that since I was using API liquid test kits they measured the ion form that i actually had to divide my ppm rating by 4.4 to find my actually nitrogen-nitrite reading. Since this was less than 1.0 ppm it was proof that the process was working. This was a little confusing to me because it was nothing you had ever mentioned before when you helped me with my last fishless cycle, and I don't know what Nitrogen it's measuring then since there is no ammonia in the tank currently, my water contains no chloramines, and the API test kit for nitrite doesn't reduce Nitrate into nitrite so I'm not precisely sure what nitrogen it IS measuring then (and it's been a while since my last chemistry class but I had thought nitrite was an oxyanion--but i digress)...... **Edit: I do see above where you mentioned to someone else about Ion form of nitrite--still not sure I understand it, but in fairness I'm not paying you as a consultant
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You can always hire me as a consultant but I am not cheap! Your nitrite test is measuring nitrite, ok. But there a couple of ways to express the units. As an example, someone from Europe might ask us how far it is from Las Vegas to LA - you might say 300 I might say 483 and neither answer is wrong they're just incomplete. You said 300 MILES I said 483 kilometers. This the same with the kits - some kits measure the nitrite ion (NO2-) other kits measure nitrite using nitrogen as the scale. The kit is not measuring nitrogen it only a scale for the units. So I say don't let your ammonia or nitrite get above 5 ppm ammonia-nitrogen or nitrite-nitrogen that gives you the units (I'm telling the scale (like miles or kilometers). The API does not measure on that scale - it measures in the ion form. So when it says 5 ppm (the top of the color chart) that is not the same as the 5 ppm that I talk about - they are different units or scales. The conversion is that 1 ppm of the nitrite-nitrogen equals 4.4 ppm of the nitrite ion. So that is why when you say you have between 4 or 5 nitrite in the scale I work with that is around 0.9 to 1.13 nitrite-nitrogen.
From this you should be able to see that any concentration of nitrite in your tank above about 1 ppm nitrite-nitrogen is going to register on your kit at the very top end. You cannot tell is the real value is 1 or 1.5 or 3 or 5 ppm nitrite-nitrogen because with that kit you are off the high end of the scale. This does not mean the kit is bad, not as all. It just means you don't have way to measure in the higher range of nitrite that you have so it seems like the cycle is stuck because every time you measure it's above the 5 on the scale. - does this make sense?
