Nitrates didn't go down after water change

[125gSW]

Am I doing something wrong or is API test kit being wonky?

Did a 20% change and normally I always see the nitrate drop as it should. For the first time after my waterchange today, my nitrate didnt budge a bit. Is it because I didnt siphon the sand enough? Not enough CUC (I only have around ~5 snails in a large tank)? or is the API test kit being weird? All my other parameters came out perfect so this is confusing. I'll be doing another 20% change soon, and if it doesnt go down, any advice how to deal with this?

 

[Randy Holmes-Farley]

I doubt that kit is capable of detecting a 20% change reliably.

What results did you see?

 

[125gSW]

I doubt that kit is capable of detecting a 20% change reliably.

What results did you see?

Ammonia at 0 ppm
Nitrite at 0 ppm
Nitrate at 40ppm (FOWLR tank)

Usually I'll notice a color change in the test tube but this time it was literally the same exact color

 

[NY_Caveman]

Did you use RO/DI water or tap? I ask because some taps have high Nitrate. I agree with Randy too. Although I think API tests get a bad rap, I will say their Nitrate test kit has been the least reliable for me. It is also their test with the most variables while testing too (two solutions, bottle shaking, etc.)

 

[125gSW]

Did you use RO/DI water or tap? I ask because some taps have high Nitrate. I agree with Randy too. Although I think API tests get a bad rap, I will say their Nitrate test kit has been the least reliable for me. It is also their test with the most variables while testing too (two solutions, bottle shaking, etc.)

RO/DI, which test kit would you recommend for Nitrate? The process is annoying for API

 

[NY_Caveman]

RO/DI, which test kit would you recommend for Nitrate? The process is annoying for API

Not sure. I used API for years for salt and fresh. I have the Red Sea test kit now, but am starting up for a new build and have not used it yet.

 

[tankstudy]

Ammonia at 0 ppm
Nitrite at 0 ppm
Nitrate at 40ppm (FOWLR tank)

Usually I'll notice a color change in the test tube but this time it was literally the same exact color

20% water change should bring it down about 8 ppm nitrate, leaving you with 32 ppm nitrate. I just pulled out my api master kit chart and there isn't a 30 ppm range. More than likely your going to see similar color to 40 ppm. If you didn't exactly do a 20% water change, say 19% only, anything less will draw you even closer to 40 ppm and show you a color that may seem like it hasn't moved a bit.

A 50% water change would drop your nitrates right in half, bringing you to 20 ppm nitrate. This would help confirm your water changes are still effective but more than likely, your test kit just can't show you it's actually happening when the difference is actually too small for it.

I would run this test first before chasing down anything else.

 

[slayerhellfire]

Am I doing something wrong or is API test kit being wonky?

Did a 20% change and normally I always see the nitrate drop as it should. For the first time after my waterchange today, my nitrate didnt budge a bit. Is it because I didnt siphon the sand enough? Not enough CUC (I only have around ~5 snails in a large tank)? or is the API test kit being weird? All my other parameters came out perfect so this is confusing. I'll be doing another 20% change soon, and if it doesnt go down, any advice how to deal with this?

hey I just had this issue, long story short nitrates were t 80!!! yeah, this was after dosing sodium nitrate and it wasn't raising them cause my API kit kept reading zero, but...the kit was expired lol so my nitrates were prob high to begin with and I kept fueling the fire, got a new kit there down to 5 now. Only way I would of known is comparing it to a another kit lol

 

[Randy Holmes-Farley]

Ammonia at 0 ppm
Nitrite at 0 ppm
Nitrate at 40ppm (FOWLR tank)

Usually I'll notice a color change in the test tube but this time it was literally the same exact color

The water change certainly dropped the level. I just don't think one can (or should even try) to judge nitrate levels so precisely (40 ppm to 32 ppm) using a kit like that.

 

[tthouston]

The quickest way to know without spending any more fresh salt water is take some tank water to your LFS to verify. Second, you can retest again after a few hours. Third, Nitrate 40ppm is normal you don't need do another water change....just feed less a little bit. IMO

 

[125gSW]

You guys are right, I'll worry about it after I do a few more and I dont see a change. Maybe it wasn't as much of an effect that I thought it would be.

Trying to hustle it down to 0ppm, excited to convert it to a reef within the next couple months

 

[Randy Holmes-Farley]

You guys are right, I'll worry about it after I do a few more and I dont see a change. Maybe it wasn't as much of an effect that I thought it would be.

Trying to hustle it down to 0ppm, excited to convert it to a reef within the next couple months

Don't aim for 0. Aim for 5 ppm.

 

[125gSW]

Don't aim for 0. Aim for 5 ppm.

Didn't know that! Why do people always tell me everything must be 0ppm? so is 5-10ppm a safe range? going to be mostly Softies and some easier end LPS

 

[NY_Caveman]

Yes. 5-10ppm is good for those. They generally like the water slightly “dirty.”

 

[ncaldwell]

I've had softies perfectly happy in the 20-40 range, as near as I can tell they like it on the higher side. If you are looking for lower nitrates I like my red sea low range test kit. It does low range(0-4) and regular(up to 40 I believe). I could potentially see some negative effects of 40+ on some lps though

 

[NY_Caveman]

If you can keep it stable in that area around 5ppm with a certain level of feeding (input) and appropriate percent of water changes (output) your soft corals and LPS should do well. The onus is on you to discover the best feeding and water change practices to find that balance for your specific system.

 

[NY_Caveman]

I've had softies perfectly happy in the 20-40 range, as near as I can tell they like it on the higher side. If you are looking for lower nitrates I like my red sea low range test kit. It does low range(0-4) and regular(up to 40 I believe). I could potentially see some negative effects of 40+ on some lps though

@ncaldwell is correct that higher levels can work. I did not mean to imply it must be 5%.

 

[ncaldwell]

Just throwing out some personal softy experience. It's good to keep them lowish but not necessary to chase numbers like sps

 

[rosshamsandwich]

hey I just had this issue, long story short nitrates were t 80!!! yeah, this was after dosing sodium nitrate and it wasn't raising them cause my API kit kept reading zero, but...the kit was expired lol so my nitrates were prob high to begin with and I kept fueling the fire, got a new kit there down to 5 now. Only way I would of known is comparing it to a another kit lol

how did you lower your nitrates down from overdosing?

 

[slayerhellfire]

how did you lower your nitrates down from overdosing?

water changes lots of them , 50 gallons one day, 30 the next and 30 few days after that. I was able to move all my rock to my sump as well cause I have lots of room and I siphoned my sand bed really good