Fresh Mixed Salt Water testing high in Nitrates

[kevin318]

Ok, I think that I'm losing my mind. I have a Red Sea e-170 max AIO set up in my house and I love the tank, very easy. 40 gallons after rock displacement. The rock in the tank is 20 years old, this set up is just over 1 year. I use API test kit for calcium, PH, and Magnesium, and Hanna for Alk, Phosphate, and Nitrates. I have some SPS, LPS, softies, zoas, montiphora, flavia, and some birds nest corals. I have four fish, two clowns, a wrasse, and a tomini bristletooth tang, 8 hermits, 5 to 10 snails. I dose 10ml calcium and 9.5m. of Soda Ash daily.

I use RO water that test at 3 ppm and I use Instant Ocean Reef Crystals. When I got my Hanna test kits I was excited, finally accurate readings. Here are my parameters, Salinity: 35ppm, Alk: 10.1, Phosphate: .03, Magnesium: 1425, PH: 8.1, Temp: 78, Nitrates: 24.5. I have been trying everything including dosing NoPox 4ml per day over the last 3 months trying to get my Nitrates down. I can't feed any less than I do, the fish will starve. I use frozen Mysis shrimp, and Ocean Nutrient Reef Flakes. I turn all of the pumps off while feeding and they eat everything that goes in the tank.

At my wits end, I decide to do a large water change, 20 gallons or 50%, and got no real change to speak of. I go another another couple of weeks, 10 gallon weekly water changes, they are not coming down. Today I decide to do a 35 gallon (87.5%) change, this has to help. Well I started with a Nitrate level of 24.6 and after the water change I'm at a Nitrate level of 26.9.......what???? So I tested fresh mix, 26.9 ppm. How? I not one to chase numbers but this is driving me nuts.

Can RO water at 3 ppm be high in Nitrates? I can't imagine. Has anyone ever gotten a salt mix that mix up with high Nitrate levels? It has to be one of two things now, either the salt is bad or my test kit is measuring incorrectly. I am absolutely following the directions to a tee. Reccomendations please, I'm about to give up on testing for Nitrates and let them fall where they fall. I feel bad for the animals though.

 

[JedClampett]

I think the standard for reef safe water is RODI water? I’m not sure the exact difference between RO & RODI. I use distilled

 

[Jekyl]

Never sure what you're getting when not using zero TDS. I'm picky but I dump out 1tds water when my filters need replacement. Not saying this is for sure your issue though.

 

[kevin318]

I think the standard for reef safe water is RODI water? I’m not sure the exact difference between RO & RODI. I use d

Never sure what you're getting when not using zero TDS. I'm picky but I dump out 1tds water when my filters need replacement. Not saying this is for sure your issue though.

One of my next options is to go DI but I don't understand that if I'm using a salt mix that claims zero Nitrates and I use water at 3 ppm, how do you end up with 26.9? DI is only going to take me from 3 ppm to 0 ppm. This one is a mystery to me.

 

[Uncle99]

If source is 3ppm and it was all nitrate, which is not likely, then that doesn’t create 24.5ppm, unless your system is new, you feed to much, or do not have any corals to mop that nitrate up.

 

[Jekyl]

It's not ppm it's tds. I feel things can be worse with drinking water this time of year also. Think of all the pesticides and fertilizer leaching into the water during the spring.

 

[Uncle99]

My meter reads TDS in ppm, it could be 1ppm CA and 2ppm Alk, which would be a good thing....no?

if not, help me understand what the TDS metric is?

 

[kevin318]

It's not ppm it's tds. I feel things can be worse with drinking water this time of year also. Think of all the pesticides and fertilizer leaching into the water during the spring.

My TDS meter reads in Part Per Million.

 

[Jekyl]

My meter reads TDS in ppm, it could be 1ppm CA and 2ppm Alk, which would be a good thing....no?

Or it could be 1 part copper 2 parts chlorine. I'm no expert, far from it. However it's either the salt or the water. Bolstering the filtration would rule out one possibility.

 

[Uncle99]

Or it could be 1 part copper 2 parts chlorine. I'm no expert, far from it. However it's either the salt or the water. Bolstering the filtration would rule out one possibility.

Fully agree with that.
I just wonder if the TDS probe itself is really that close.
The OP posted using RO water, I didn’t see the DI part and that would certainly result in not getting a 0ppm.
Maybe I missed that.
Cant see this as a problem, but nitrate needs to be halfed.
They could do a 50% change and nitrates should drop by 50% (ish)
Then if you measure and you still get 24.5ppm, your meter is not functioning properly.

 

[JCM]

Maybe a faulty test, try with a different kit to verify.

Are things looking bad in the tank? Personally, I wouldn't be doing massive changes over 25 ppm nitrate. You say you're not one to chase numbers, but sounds like that's exactly what you're doing.

 

[kevin318]

All,
Thank you for you input, all very helpful. The problem was that I wasn't using RODI. My freshly mixed salt water tests at 1.9 ppm of Nitrate and it was skewing my test results.
When I first used my Hanna checker it said that I needed to do the dilution process where you take 1 ml of water and add 9 ml of fresh salt water. Then when you get your reading, multiply by 10. That great but I didn't realize that I had been multiplying the 1.9 ppm in my dilution process which add 19 to 20 ppm to my actual number. The dilution process assumes that you are using RODI which would be at zero Nitrates.
As a result, I have turned off my NoPox dosing pump, because as of an hour ago after testing it correctly, I'm at 1 ppm. LOL
I will be adding a DI cartridge to the system on Monday.

 

[kevin318]

Maybe a faulty test, try with a different kit to verify.

Are things looking bad in the tank? Personally, I wouldn't be doing massive changes over 25 ppm nitrate. You say you're not one to chase numbers, but sounds like that's exactly what you're doing.

JCM,
I know what it looks like but my definition of chasing numbers would be worrying about my Nitrates being 10 ppm and chasing 8 ppm. Because I'm somewhat newer to keeping coral, everything I've read talks about keeping Nitrates down. Not zero but certainly not 26.
It was faulty testing on my part, a little new at this game of keeping coral.

 

[JCM]

JCM,
I know what it looks like but my definition of chasing numbers would be worrying about my Nitrates being 10 ppm and chasing 8 ppm. Because I'm somewhat newer to keeping coral, everything I've read talks about keeping Nitrates down. Not zero but certainly not 26.
It was faulty testing on my part, a little new at this game of keeping coral.

Glad you got it figured out!

For future reference, while 25 is higher than you see recommended its not high enough to kill even the most fickle corals. A 90% water change is more likely to harm them than 25 ppm nitrate.

 

[kevin318]

Glad you got it figured out!

For future reference, while 25 is higher than you see recommended its not high enough to kill even the most fickle corals. A 90% water change is more likely to harm them than 25 ppm nitrate.

Thank you, I appreciate the help. I was starting to think that I was crazy and it turned out to be user error! I hate to admit but this has been a problem for me since February, that why the massive water change.

 

[JCM]

Thank you, I appreciate the help. I was starting to think that I was crazy and it turned out to be user error! I hate to admit but this has been a problem for me since February, that why the massive water change.

Luckily only a problem for you, sounds like the tank inhabitants have been doing just fine! Best of luck with it.

 

[Rmckoy]

I think the standard for reef safe water is RODI water? I’m not sure the exact difference between RO & RODI. I use distilled

Ro is only reverse osmosis
The di stands for deionized . Which is not required but suggested .

 

[kevin318]

Ro is only reverse osmosis
The di stands for deionized . Which is not required but suggested .

Correct but when you are using it to dilute and then using a multiplier, its a big problem. I thought my tank was high, turned out to be low. I don't believe this would have happen had I been using RODI.

 

[Rmckoy]

Correct but when you are using it to dilute and then using a multiplier, its a big problem. I thought my tank was high, turned out to be low. I don't believe this would have happen had I been using RODI.

I bought the same kit .
hated it from the first test for that dilution process .
I went back to using salifert

 

[kevin318]

I bought the same kit .
hated it from the first test for that dilution process .
I went back to using salifert

I can't say that I hate it but Salifert is definitely quicker and your less likely to make a mistake like I made!