Nitrate & Alkalinity ?'s

About every 3 weeks I do a 30 gal water change(50%), but my water never changes. Everything's good even at the end of the 3 weeks except nitrates stay around 20. Why aren't they going down after water changes? It's not the water i'm getting cause I test it before i put it in and it's < 5, and it's not the test i'm using cause i have 2 different nitrate tests and they read the same. Is 20 terrible? if so how can i lower it?

My Alkalinity is 13. It's supposed to be between 8 & 12. Is that bad? how do i correct it?

 

20 is not awful as a general rule, for nitrates to have an adverse effect on fish, they would have to be astronomically high! But i notice you have an anemone so hopefully someone else who knows more about anemones will chime in on that one.
Also im pretty sure you should do frequent small water changes as opposed to seldomn big ones.

 

20ppm is sort of normal and it could be do to your salt mix, unless you are using real sea
water witch is full of it. also the size of your tank play a big role in it, the smaller the more frequent you need to change some of your water. But you need to be a little more specific!
how many fish, rock, filtration etc...etc!

 

It's all in my signature. and i do use real sea water ( most fish stores down here have it) but i test it first and it's perfect.

 

if its a reef tank then NO3's above 10 is not good and if its a reef for SPS and or LPS corals then NO3 that are even detectable then its to much.

Test the source water not many places around Fl. that I'd use the water from.. I know fl pretty well just not sure where Weston is ?

The Dkh could be like it is at the expense of the Calcium and Magnesium where are those levels running at ?

I'd myself would try to get the NO3 lower then 20. But like already mentioned 20 is not life or death But its about 20 higher then I'd like to have in my tanks.

 

Weston is just west of Ft. Lauderdale. And the source water is good it's <5. Calcium stays around 420 and i don't know what the magnesiium is cause i only tested it once w/ a friend's test.

 

I disagree, I also have tested the water and it has 0 No3. I also have 20ppm No3 for the longest and I dont see anything wrong with my corals. What could be causing it? A number of things; over feeding, too many fish, not enough LR, not cleaning out sponges and filter pads and/or not having an efficient biological filter system. Luna

 

When you guys say real sea water, do you mean that you go down to the beach and scoop up water?

 

NO......NO Thats a no-no. My LFS gets it from a guy who goes out a couple miles out and a couple of feet down and sucks up a couple of gals.

 

No! My LFS says he gets it from from a 3rd party who supplies many LFS's around here and he supposedly goes about 20 miles out and 20' - 80' deep. Then, I was told, there's an additional cleaning process (don't know how or what) to eliminate any unwanted elements. Luna you're kinda near me. What LFS do you use?