No nitrates... Should I worry?

[WhiteTang]

Hi everyone!

It has come to my attention that I no longer read any nitrates.
My tank is 7 months old. When I started the tank the Red Sea test kit would go off the charts until the tank cycled. After that the nitrates declined steadily until they were completely undetectable and has been like that since.
I have a 16g nano tank. with two aprox. 1,2 inch fish. I feed once or twice a day (but not everyday) and never too much. My water changes are 20% every week.
Shouldn't I read at least some nitrates?
I have even tried to leave the tank without a water change for 2 weeks in a row and there were no detectable nitrates.
I am sure that the test kits are good because they are the same that I used when I cycled the tank (no, they have not expired).
My filtration is (besides the live rock) sponge for detritus, a little activated carbon mixed with phosguard, some purigen and a litre of Seachem matrix (more biological filtration).
Could it be that the Matrix is actually doing what it advertises? Help remove nitrates?
What do you think?

 

[novadan67]

I wouldn't worry. My tank is about 5 months old and I haven't seen any nitrates for several months. I always thought it was because of my HUGE skimmer and chaeto fuge... but you have neither, so maybe something else it taking care of my nitrates in my tank. Like you, I know my test kit is fine since I use it on my cichlid tank and it always shows nitrates. I don't worry about it... I see it as a good thing!

 

[itsmorefun]

No that's ok

 

[coralsnaked]

how are the phosphates? Is this FOWLR ? Or are you trying to grow corals? If you are growing corals you need a little PO4

 

[WhiteTang]

how are the phosphates? Is this FOWLR ? Or are you trying to grow corals? If you are growing corals you need a little PO4

The thing is I don't have a phosphate (PO4) test kit. I have a few LPS corals (Acans, Favia, Trachyphyllia and Eyphyllia). All corals seem to be doing great. Even the Favia which is a super slow grower. The Acans stopped puffing up like they used to but I contribute that to the new (stronger) LED lightning that I got a few months back. The Euphyllia on the other hand has split and has doubled in size. I find that odd since I know this coral likes "dirty" water better than super clean. Of course I do spot feed them all so it might be that.
Im not sad that I don't have any nitrates, its just that when I started the hobby I read A LOT of posts, articles etc. All said that nitrates need to be removed manually. So If Im not removing them via water changes WHAT is removing them?

 

[Waters40]

I am guessing the combination of live rock and water changes are removing them. De-nitrification occurs deep within the live rock. My tank has been set up for almost a year and I have never recorded any nitrate.