Help with NO3

[sean9_man]

Hi guys, I'm in need of some serious help. I've been feeding for a little over 3 years now and I've had a very healthy tank until recently pretty much 95% of my corals all died.

The culprit was NO3. Now I've had no3 before in my tank but not like this. My 180litre tank has been running for a year and a half and I've always had the same ritual with it so it made no sense for the crazy NO3 spike which was 100. Then all my LR started turning black!

I then thought it was the perfect time to drain everything, clean all rocks and redo Aqua scape and start all over. But again after a few weeks my LR started turning black again. Obviously the no3 was still high. I then tried to test RO water and water without RO. It also showed high levels of NO3. Very close to 100. By now I thought my RO must have something wrong with it so I went and bought a new one yesterday. Installed everything this morning and tested water again. Still NO3 so I think something is contaminating my water. There's a little construction going on next door so I don't know if that's affecting it.

The only way I know how to bring it down is with water change but it's no use when new water is full of NO3. I do use the Red Sea no3 and phosphate dose but it's done nothing for me recently. If anyone can help me in anyway would be great. I've learnt lots on this forum and I know there are lots of experts out there so I'd appreciate it if someone can help me.

Thanks

 

[hart24601]

Do you have a DI system after the RO? I don't think RO is very effective at removing nitrate, it reduces it but the DI takes it to 0. How old and what brand of test kit, that could be off too. If the city water is really that high, over 100, that is well above the legal limit of 10ppm:
Basic Information about Nitrate in Drinking Water | Basic Information about Regulated Drinking Water Contaminants | US EPA
If that is the case I would call the city.

I got tons of nitrate once when my RO/DI got old and leaked a bit of nitrate, since my tank evaporates 1-2g a day, it didn't take long to have a lot of nitrate in the tank with topping off 2-3ppm nitrate!

Once you get your top off water to 0, I like carbon dosing to reduce in tank, but have to get that source water to 0 1st.

Ro/DI can get your water to 0, but you might go through lots of DI if the source water is really 100ppm (but that high is dangerous and the city or someone needs to fix that), get water from LFS or even hyvee or walmart's fill your own jugs. Take a TDS meter or do a nitrate test on those. The stores here have the TDS reading from the last service and they are pretty good.

 

[sean9_man]

My unit is a RO/DI unit. I'm living in Hong Kong so I don't know why it's suddenly turned so high in the pass 1-2 months. My only guess is construction next door as someone is building a new house. Otherwise I've never had problems with no3.

I just did a little research online and said my psi meter needs to be at 40-50 to work properly so I'm going to give that another crack and see how it runs. I doubt it will bring it down to 0 though.

I'm using the Salifert test kit and I just bought it recently so it's definitely not the test kit.

Thank you so much for your reply. I just hope I can fix this problem soon because it's driving me up the wall!

 

[hart24601]

That is a pretty big problem! Is the DI new? Maybe you can hook up another DI after it, some people here run systems like that. Hopefully someone else can give some advise, I don't know how long a DI will work with that much nitrate, but when it's working there shouldn't be any nitrate that makes it past. What PSI were you running the RO/DI at? Mine runs at 80, which is just the city water pressure.

 

[sean9_man]

Yes my whole RO/DI system is brand new so it should be good. I just controlled mine to 50 as I just saw a video on YouTube that it's best quality at that level.

I just tried again and got this.

 

[sean9_man]

So I went on the water supplies website and saw the units for the no3 level. It shouldn't be more than 2.0 which shows mine is way off....they going send a guy over to inspect the water in the next day or two and hopefully I'll have some clean water soon..