Discrepancy

[gwand]

My API dip stick gave me a nitrite reading of 1 ppm In one of my tanks. This surprised me so I tested the water again with API Freshwater Master Test Kit. The reading was 0 ppm. Which API test should I believe? Thanks.

 

[MattW3344]

I've used both and found the master kit more useful and accurate. The strips can easily be contaminated even futile from what others have said. When I had my old tank I used the test strips and had a few occurrences of completely different results within a short period of each other.

 

[WhistlingBadger]

Strips can be a good quick check to see if anything is wrong, but if I get an unexpected result I always back it up with a liquid test.

 

[jaylach]

Liquid tests are usually more reliable. I don't know if I'm right on this but I suspect that the lesser accuracy of strips is due to their being 'sensitive' to the environment.

This is speculation as I've never used strips but would believe that they are litmus paper impregnated with test chemicals. Shoot, to be honest, I don't even know how the strips are packaged... individual sealed strips or a single container holding the strips? If a single container every time it is opened the strips are subjected to humidity in the air which, I would think, could cause degradation of the strips which could easily cause false results. As an extreme, and probably silly example, let's say that the container for the strips are in your kitchen and you are cooking hotdogs. Most brands of dogs are high in nitrates. While you are cooking the dogs you open the container to get out a nitrate strip. The entire container of strips have now been exposed to a small amount of nitrates that are in the air. The strips are now contaminated and could give a false reading due to the contamination. The bottles of chemicals with a liquid test kit are much less susceptible to such contamination.

Like I said, this is all speculation but it makes sense to me.

 

[Ceez]

My API dip stick gave me a nitrite reading of 1 ppm In one of my tanks. This surprised me so I tested the water again with API Freshwater Master Test Kit. The reading was 0 ppm. Which API test should I believe? Thanks.

How often are you testing? I've seen so many different theories on this. Just curious what yours is. Personally I check TDS more than anything else because I want my fish to have the highest quality water to breed. I will from time to time run a full array of tests just for peace of mind because I like to overthink.

I've watched a lot of videos from experienced fish keepers who say they hardly test at all except when establishing a tank. They say that they watch their fish so much they know when somethings wrong and that's when they start testing but normally they don't test at all. I'm not that confident personally so I test once every month or two.

 

[Ichthys]

Believe the liquid as long as it's in date and you're using it properly, banging as well as shaking. Otherwise you'll get false readings. Throw the strips away, they're useless. If they weren't "just for fish" they'd have been banned a long time ago under the trades descriptions act.

 

[GaryE]

I'm a tds user myself. I've used reagents and strips and they match up, but my cheap tds meter gives me what I need for breeding, and I use tap with no doctoring. So the water's predictable.

I'd trust the reagents more, if they aren't expired. I have never had any problem with strips, and they give you a lot more useful info than the API not very masterful kits, but they are vulnerable to dampness. The liquid tests are good.

 

[gwand]

How often are you testing? I've seen so many different theories on this. Just curious what yours is. Personally I check TDS more than anything else because I want my fish to have the highest quality water to breed. I will from time to time run a full array of tests just for peace of mind because I like to overthink.

I've watched a lot of videos from experienced fish keepers who say they hardly test at all except when establishing a tank. They say that they watch their fish so much they know when somethings wrong and that's when they start testing but normally they don't test at all. I'm not that confident personally so I test once every month or two.

I was testing only because a fish died in a recently cycled tank. In my established tanks, I rarely test.

 

[WhistlingBadger]

I don't test my home tank; I just keep an eye on my fish and do big water changes every week. The dentist offices' tank I test at least a couple times a month, because it's more densely stocked, I only see it once a week so I can't rely on observation as much, and I guess I'm just more careful when I'm spending other people's money.