I know Marine Depot indicates this is accurate for fresh water but Hanna states otherwise. Given the differential in price, I suppose you could argue a conflict of interest...
BILL H.
Verified Reviewer
12/31/20
Q: CAN THIS NITRATE TESTER BE USED IN A FRESH WATER AQUARIUM AND GIVE ACCURATE RESULTS?
Answers (1)
Hanna Instruments
01/04/21
A: The product (HI781) is designed for Salt water only, we do make a Nitrate colorimeter for fresh water. the product code is HI97728
pablos, you could either do serial 1:1 dilutions with distilled water, then multiply your results by 2, 4, 8 or use their dilution method which gives results at .1 actual value, multiply the meter value by 10 and your range is 0-50
Tom, love the rant. My goal with nitrates is more the "canary in the coal mine" model. With (what I think are) adequate water changes if the nitrates start climbing then something is wrong. Given the desire to achieve stability, my plan is to monitor TDS, Nitrates, kH and gH, in addition to pH as an assessment of tank health. Might even look at the fish to see how they are doing Given your success with plants I would guess you might actually have to add nitrate fertilizer. The canary model is compromised if the plants are eating all the nitrates but even then if nitrates start climbing something is wrong...
This is the cheapest accurate nitrate test:
https://www.hach.com/dr-900-multipar...id=15684103251
It can use the chromotropic acid method which isn't a random number generator like the traditional tests:
https://www.hach.com/nitraver-x-nitr...53&callback=qs
I'm a fan of this rant. I struggle to get my nitrates to stay below 20 in my planted tank but my fish are happy so I've stopped obsessing over it. That said, I've been using only the stock fluval bio cylinders and recently added matrix so maybe the extra surface will help.
Have you tried hanna instruments products by chance?
I hang around 10-15ppm. It's not something I obsess over at all, but in the odd event that it creeps up to say 25ppm, etc, I'd like to know so I don't add ferts to the tank that day/week for example. If it gets really low, I'll know to add more ferts as well.