Lowering Nitrates

Hey everyone Ive really enjoyed getting into this hobby, however I am at a stalemate. I cant seem to lower my nitrate below 40ppm.

I have a 150 gallon tank with a few softies: gsp, hammer, zoas.
Six fishes: 2 sm clowns, 1 med desjardini sailfin tang, 1 bangaii cardinal, flame and coral beauty angels. The tang gets fed nori twice a day, and I also feed the angels a single cube of frozen shrimp from the lfs once a day.
I am running a filter sock and I change it once a week. The sock is only half submerged and never overflows before I change it out. My sump has a nautilis te skimmer, 3 little fishes reactor with rowaphos, bubble trap with filter media and 2 mag 9.5 return pumps. I also have some chaeto in the sump under a home depot grow light 65w I believe.

I do water changes however im not very consistent with them. Probably about 20-25 gallon change every two weeks or so. I really am looking to reduce nitrates with the chaeto, not water changes.

What suggestions do you guys have to get the nitrate levels lower?

 

Any chance you rinse your frozen before feeding? Twice a day may be a bit much. What goes in must come out How often are you cleaning your filter media? Good source of nitrate traps. Also what sort of flow you got going on in your tank? Could be a build up of detritus on the LR.
Personally I look first for the possible causes. Then go for the fix. Another idea, what no3 test are you using?

 

I would say to change that sock more often. I change mine every 3 days, because it gets really brown. Try to change your water every 10 days for a month and see if that will lower it.

 

I dont rinse the frozen cubes, but I do let it thaw before feeding. Only the tang gets fed twice, 2in x 6in strip, and he begs the rest of the day haha. The angels are fed once daily.

It could be a flow issue, I have two powerheads, not sure the make/model, and the returns pumps, mag 9.5, which fork the exhaust throughout the back of the tank. I have a cuc from reef cleaners designed for my tank, but im thinking it may not be sufficient. I ordered a medium intensity crew.

I really hope I wont have to change that sock every three days, Im trying to reduce the amount of daily maintenence as it is.

 

What are you using for your source water? Tap? RO/DI?

 

I took over my 75g tank when someone else had let the nitrates climb greater than 160ppm which is as high as my test would read. It took several very large water changes before I read anything less than the max, so I estimate the nitrates were up over 200. After a few months of steady progress from water changes and reduced feeding I reach a standstill around 30ppm nitrate. I installed an aquapure nitrate filter and though it took a month to build its bacteria to the point where it was consuming nitrates it did start working. The combination of that and 15% water changes every 2 weeks-ish has kept my nitrates around 0 or in the single digits at least. The Nitrate filter requires consistent adjustment of flow and injection of cheap vodka (twice weekly for me). I recently was away for vacation and returned to 12ppm nitrates. Darn unreliable tanksitters. I plan on modifying my sump to include a fuge-like area to grow macro algae to further help in Nitrate export.

Good luck with your tank

 

is installing a refugium an option for you?

 

I am at 20ppm which I'm OK with; though I do wish it was lower. I do have a fuge, but may need to swap out the algae. Water changes once a month. My 5 stage RO/DI filter is coming today from BRS! Can't wait--no more chemicals, and clean water. Hoping this might help too. My filter socks I change out every 5-7 days which may not be enough. I wish I didn't have to use them but they are great at stop microbubbles from getting in my DT.

 

First thing I would do is when its time for a water change, get a small power head and spray all the rocks and see what comes out and gets collected in the filter socks. Then whatever is left over I would siphon out with the water change. I would perform that for every water change. I would definitely look into, if its in the budget, getting power heads for more circulation to keep detritus suspended in the water column and overflow into your filter socks.

 

Im using rodi water for all my changes. I Have been considering doing a remote refugium, I have room for it under the stand but havent thought about dimensions much.

I think flow may be the issue, I used a turkey baster to blast the rock and all sorts of nasty looking sand/sh#!t came out and our tanks been cloudy since. Most likely going to purchase a third powerhead shortly.