nitrates are driving me up the wall

[mike31154]

So other than the nitrate readings being what they are, how is your tank doing? Doesn't sound like you have any major problems other than the nitrate readings themselves driving you up the wall. The diatoms on the sand can be taken care of with an occasional blasting from a turkey baster to put them into suspension. Your skimmer will take care of the rest.

I've had my 75 for about two & a half years now and recall some ups and downs with nitrates. My set up as far as tank & live rock is all from previous owners and there wasn't much of a cycle to speak of on initial set up. Subsequently there was a period of slightly elevated nitrates, then they dropped to 0 only to come back up to about what you're experiencing at about the 1 year mark. No matter what I tried, I couldn't get them down, drove me up the wall. However, none of my livestock appeared to be suffering or stressed, although I didn't have much in the way of corals. Not long after scoring some Chaetomorpha algae (thank you Myka) and adding a VorTech for water movement, the nitrates gradually became undetectable.

I'm too new at this to provide expert advice in this regard, but this has been my experience. Not sure whether it was the Chaeto, additional flow or just the system itself maturing to the point where the biological balance was at the point of taking care of whatever nutrients were causing the elevated nitrates. Might be a combination of a number of factors. Each system is more or less unique, don't let nitrates drive you up the wall. Keep an eye on your livestock and general tank condition, water changes and some macro algae should eventually take care of it.

Other factors noteworthy from my experience:

I feed what many folks would consider generously, I don't like to starve my fish at the expense of a super low nutrient system. I feed frozen, granular as well as flake and any changes I've tried to make in that regard did not appear to impact my nitrate readings significantly;

I now have a few coral specimens, softies and several LPS;

I've only recently changed to using RO/DI from treated tap water and must say, that was a wise move as this has cut down on algae issues;

I have run GFO in a canister filter (I don't have a sump at this time) but it appeared to have nil effect in phosphate readings, these have always been very low in my system. I still run a small amount of carbon in my canister which is otherwise empty;

My skimmer is definitely old school, DIY air stone, counter current but it works well, is quiet and uses little power.

At any rate, I'm confident in saying I have yet to lose any livestock due to elevated Nitrates (when they were elevated), so I'm not sure a reading even up to 20 ppm is all that harmful, other than stressing the system owner. SPS dominated system owners obviously need to aim for better numbers than that. You mention that you do not have a hair algae problem so that's a bonus. I admit that that has been an issue with me in varying degrees. I believe the change to RO/DI will gradually take care of that. Good luck with your system and I wouldn't change too much too fast due to your nitrate readings. Keep an eye on the livestock more than anything as an indicator of system health and give it more time.

[Myka]

Good advice Mike!

[68shelby]

I literally have no algae, all the fish are healthy, the clowns lay eggs every 2 weeks unless I **** them off with a good tank cleaning seems to disrupt there cycle. Corals are all growing especially the mushrooms. No my biggest issue is the water changes. I use to do 5-10% a week and my nitrates just started to come on. now I am at 25-30% almost weekly and am getting tired of getting nowhere with it. Its expensive. I use ocean pro salt and bottled water. Where do I draw the line do I go back to 10g a week and watch how high the nitrates climb? or do I keep spending $250.00 a month on water changes. Thanks for the input I will definitely consider several things mentioned

[mike31154]

Yow, 25-30% water change per week, that's heavy duty. I do the same percentage but only about every 16 to 21 days. Why not start monitoring nitrate levels closely at the time you would ordinarily do a water change and extend a few days to see what happens? Take it one day at a time after that and if it gets out of hand, then do the water change.

Are you running the system with a sump? You mention bottled water, is the source reliable? Might want to do a quick TDS check on your source water, although you say there is no algae in your tank.... maybe that's the problem, algae takes up nitrates quite efficiently, but of course the wrong kind is a pain.l

[68shelby]

Yes I have a 45 gallon sump that will have a refugium in it as soon as I can get a light wired in. Right now the sump is basically 5-10lbs live rock rubble (inlet) under and over to the skimmer chamber then over to the refugium bed (currently about 4-5" of sand/gravel and then over into the return pump chamber.
And yes I have virtually 0 algae in the tank. even the back wall that I would leave for the tangs is bare other than pink and purple coraline. I wish I had some algae for the tangs.
Water flow is 2000 gph by the main pump,(probably somewhat reduced by the fact its in the basement) and I have 2 power heads one on each side of aquarium. 100g corner round.
Water I buy at sobeys. I have tested it prior to water changes and it tested fine. I am starting to think it is the mysis shrimp I have regularly fed.

[i have crabs]

how much rock in the tank its self?, i would invest in a ro/di unit so you can control your own water i woulnd trust buying water, not to mension the cost.
growing alge in a fuge will probably be enough to get the nitrates down from even the 20ppm mark but sound to me like there isnt enough filtering going on now

[i have crabs]

you said you have no filter media correct?, so no filter socks/sponges/floss/bioballs anywhere in the system? how much rock do you have in the tank? pictures amuse us and it might help us see what your workin with.
sandbed? how old is the tank?
test the water your using for waterchanges and your tank water to compare the 2, under 20ppm nitrate isnt a death trap but can add to other issues, i dont think your tank is over stocked, the only time ive had lingering nitrates is when i employ some kind of mechanical filter since i tend not to keep them clean enough,i feed frozen mysis,reefroids,cyclopeeze daily, i rinse out the mysis and make icecubes with everything mixed in that way its ready to go and pre portioned, since i started doing this im much better at not over feeding, i never have any problems nitrates in my reef and i think i still feed quite abit over all. i have quite a bit of live rock and a decient sized skimmer but thats it for filtering. i do 25-30% change ever 4-6 weeks in my reef and its worked well.
i run carbon and gfo 24/7 but dont relate them to nitrates in anyway,

[alamo]

Are you seeing any signs of distress from your fish or corals?

[68shelby]

So got home tonight tested my nitates (hagen test kit) reads 20pm or slightly higher, disgusted I get water sample and go to LFS. They test with Elos aqua test kit Nitrates 5ppm, problem solved
Thanks to all you for your suggestions and I will still follow through on some recommendations and,
Thank you Josh @ MARINE AQUARIA

[Myka]

If you're spending $250/month on water changes, why not save yourself a few bucks in the long run and buy an RO/DI unit? You should be able to find one for under $200. Saves a lot of packing water around, plus you know what you're putting in your tank. Try testing the Sobey's water for nitrates (most nitrate kits will do both freshwater and saltwater). Also mix up some fresh saltwater (let it mix for 24 hours), and test nitrates in there.

LOL I just read your last reply as I'm typing the Quick Reply box...that's great you have your problem solved! When I'm at my wits end like that I double check test kits.