Nitrates

[chuckfu5]

I’ve been testing high for Nitrates the last while and thought it was my tank. I decided to check my rodi water after it was mixed with my salt ( Red Sea pro ) to my surprise it measures exactly the same.

So basically I’m not doing any good by doing water changes for nutrient export.

They both are measuring around 15-20 on the Red Sea algae test kit.

My question now is it the rodi water or the salt? I get rodi water from Walmart and will obviously be switching that now and going to my lfs.

 

[saltyfilmfolks]

Did you test the in mixed water?

And I don't belive Walmart sells rodi. Just ro or distilled

 

[Randy Holmes-Farley]

I'd be quite surprised if this was accurate.

FWIW, a small amount of nitrite often shows as a lot of nitrate.

 

[DSC reef]

Been using RSCP for over 7 years, never had a nitrate issue on fresh made water. I'd question your water source, RODI is not sold at walmart.

 

[chuckfu5]

Did you test the in mixed water?

And I don't belive Walmart sells rodi. Just ro or distilled

I use the Primo refillable machine. Is this not RODI water?

To your other question is I tested water in my tank and then freshly mixed saltwater. Both tested the same.

I have not tested just the water from Walmart.

 

[saltyfilmfolks]

There's no di stage there.

 

[DSC reef]

I think that's for drinking water, not the same but I could be wrong. I'd get a second test verified by another test and or try a different test kit. I'm not a fan of red seas testing kits, especially nitrate.

 

[chuckfu5]

I think that's for drinking water, not the same but I could be wrong. I'd get a second test verified by another test and or try a different test kit. I'm not a fan of red seas testing kits, especially nitrate.

Well that sucks.

Another question is how do you guys clean the crap that accumulates in the bottom of your mixing jugs?

 

[Randy Holmes-Farley]

Even being RO only, it won't have that much nitrate in it.

The EPA standard for max nitrate in drinking water is 10 ppm, and presumably this is purified by the RO by at least a factor of 10 beyond the most polluted drinking water allowed.

 

[alton]

I had a fellow reefer that used Wal MArt, he would pay attention to the inspection/filter change sticker on the filtration system. At my employers last facility, the tap water had 10 ppm of nitrate. We had a filtration system brought in. I am sure it had to do with the part of town and old piping.

 

[DSC reef]

Well that sucks.

Another question is how do you guys clean the crap that accumulates in the bottom of your mixing jugs?

I've never had any residue in my mixing buckets. I use the water an hour or 2 after mixing.

 

[Randy Holmes-Farley]

I leave the residue on the bottom and let it accumulate for more than a year (in a Brute trash can).

 

[chuckfu5]

I've never had any residue in my mixing buckets. I use the water an hour or 2 after mixing.

I have a small tank and mix 5 gallons at a time and only change a gallon or two every couple weeks so I have water that sits in a container for a few weeks.

I do keep it aerated with a pump.

 

[DSC reef]

I always use it up right away, 15 gallons a week. It won't hurt anything, like randy said, he keeps his residue year round! Lol

 

[Hans-Werner]

FWIW, a small amount of nitrite often shows as a lot of nitrate.

Just as an example: We (Tropic Marin) manufacture and sell two Nitrite-Nitrate-Test-Kits. The nitrate : nitrite factor is 100 in the ultra low range Pro version and 50 in the higher range Basic version. I am sure it is similar in other nitrate test kits too since all use the same basic chemistry in reducing some of the nitrate to nitrite and in fact measuring nitrite.

 

[Randy Holmes-Farley]

Just as an example: We (Tropic Marin) manufacture and sell two Nitrite-Nitrate-Test-Kits. The nitrate : nitrite factor is 100 in the ultra low range Pro version and 50 in the higher range Basic version. I am sure it is similar in other nitrate test kits too since all use the same basic chemistry in reducing some of the nitrate to nitrite and in fact measuring nitrite.

Thanks very much. Habib of Salifert confirmed this for their kits, but never told us the multiplication factor.

 

[Hans-Werner]

You´re welcome. The multiplication factor may vary among different test kits, depending from the proportion of the nitrate being reduced to nitrite.

 

[Lasse]

@Hans-Werner

If I understand it in the right way – if I have a nitrite of 0.1 mg/l in my sample – I will read at least 10 mg/l in nitrate with your pro test?

Another question – which salinity is your tests adjusted to ?

Sincerely Lasse

 

[Hans-Werner]

Lasse, this is correct. With 0.1 ppm nitrite you will have a 10 ppm higher reading of nitrate. Usually this is no big problem since most aquaria with low nitrate concentrations have low nitrite concentrations too. Exceptions are for example aquaria with sulfur nitrate reductors and incomplete nitrate reduction to nitrite. The nitrate reductor releases nitrite which simulates high nitrate concentrations. Then I get a call that "the test kit is not reading correct because I have a nitrate reductor and the test shows a high nitrate concentration".

The test is adjusted to and calibrated at normal saltwater conditions 35 PSU salinity but it also works with freshwater.

 

[Lasse]

Thank you – I have known this for many years but Just like Randy, this is the first time I hear a figure of how much it affects. Thank you once again for that.

Sincerely Lasse