Nitrates just won't die (Biocube 29)

[srpntmage]

I started up my Biocube 29 about 6 months ago. Media rack with purigen and chemipure elite, Tunze 9001 skimmer and lots of porous live rock in the display. I feed lightly about twice a day, a little flake, some high quality pellets and strained mysis a coupe times a week for the corals.

Currently I have 2 clowns, a watchman goby, a tiny tail spot blenny pistol shrimp, cleaner shrimp and various snails and hermits. For corals, I have zoas, a torch, candy cane, duncan, some acans, a toadstool, pinwheel plate and some ORA Pink Birdsnest.

After my tank cycled, months ago, my nitrates were off the chart. I think it was from my rocks leaching. They stayed at 180+ for several weeks and only started dropping after doing heavy water changes.

I change 5 gallons every week (my actual water volume is around 23-24 gallons), and am careful to suction out the back chambers, blow off rocks and I change my filter floss every 2-3 days.

Today my nitrates hang around 15-20ppm. My phosphates fluctuate from 0 to 0.09ppm . I started using Red Sea NoPox about 3 months ago and it has done nothing, though I have followed the directions very carefully.

Everything in my tank looks and behaves healthy, but I worry. I want to add some more SPS at some time, but my nitrate level seems too high.

Anyone have any idea what is going on? Should I be doing heavier water changes? Bio-pellets maybe? I have been considering adding a reactor, but if NoPox isn't working I assume bio-pellets won't either.

Here is my tank.

 

[LetItReef]

Maybe try a different Test kit.

 

[srpntmage]

Well, I am using a Red Sea test kit now, but I have cross checked with an API kit and got similar results. I use a Hanna checker for my phosphates.

 

[Scubafrog]

Great looking Biocub!

+1 on trying a different test kit or taking a water sample to your LFS for testing. By the looks of your tank it appears you are doing everything right. I have the exact same set up and my nitrates are always around 5 ppm. I only feed frozen brine once a day as I only have (2) ocellaris clowns, (1) bicolor dottyback, and a cleaner shrimp. My issue is GHA and brown sand since I removed my Eshopps sponges and replace with inTank and Tunze 9001.

 

[Scubafrog]

Does your Tunze 9001 foam much? Mine usually just has fizzing bubbles. It does foam some and produces some watery skim mate. It has only been running since 1/2/15.

 

[saltyphish]

I run my biocube with the intank media basket chemipure elite, purigen like everyone else. I also use the santa monica hog .5 ats in my middle chamber with a tunze 9001 skimmer as well. My phos and nitrates are always near 0. Maybe your rock is leeching nutrients back into your water.

 

[sureal00]

do something like a 50% water change twice in 7 days .Test your water you mix with salt for nitrates.

 

[saltyphish]

Yes check your make-up water for nitrates maybe they are not coming from inside the tank

 

[srpntmage]

Well, my source water comes from my 4 stage RODI unit. It reads 0 tds but I haven't checked for nitrates. I use Red Sea Coral Pro salt mix, which isn't known to have nitrates, though I guess I could check that too.

The weird thing is that Red Sea NoPox isn't working. Even with every other factor... leaching, overfeeding, bad source water etc... carbon dosing should be working after 3 months. I am not looking for 0 nitrates, just somewhere consistently around 5ppm would make me happy.

Scubafrog: My skimmer makes lots of skimate, though it does depend on how close to the water line I have it. Lower = more watery skimate. Since I am carbon dosing, though not to much effect, I run it wetter. My Tunze 9001 was producing skimate the day I bought it. Very little break in time.

 

[srpntmage]

Would doing a months worth of 50% ( 10 gallon) water changes cause problems with my livestock and corals? Since things are pretty happy, I am afraid of shocking things by changing out too much.

 

[srpntmage]

How on earth do you fit a santa monica hog .5 ats in your middle chamber with a 9001 and media rack lol. I would love to run an algae scrubber, but I can't find any room.

I run my biocube with the intank media basket chemipure elite, purigen like everyone else. I also use the santa monica hog .5 ats in my middle chamber with a tunze 9001 skimmer as well. My phos and nitrates are always near 0. Maybe your rock is leeching nutrients back into your water.

 

[Soylent Wrasse]

Try the phosphate removing pads as a pre-filter. It will help pull stuff out (the mechanical part) and should help with phosphates as well. They are pretty cheap in the $6-8 range from Amazon as well as other places. Heck I think Petco even carries them now.

 

[sureal00]

if you match salinity and temp it should be no problem.

 

[mike007]

You might try feeding less. Many of us do not feed corals they can get what they need from the fish food we feed. Only feed once a day and make sure all food is eaten and non of it strays into rock or hits the bottom. Also i have had better luck dosing vinegar . Nitrates are caused by excesss nutrients which normally are caused by overfeeding.

 

[Mike in CT]

Might try carbon dosing!

 

[Randy Holmes-Farley Verified Community Expert]

There are lots of good ways to reduce nitrate. These include growing macroalgae, using an algal turf scrubber, organic carbon dosing of various sorts (vodka, vinegar, biopellets, etc.), denitrators (carbon and sulfur types), and skimming.

I have an updated article on nitrate coming out at Reef2Reef on February 1.

 

[Reefing Madness]

Might try carbon dosing!

Took the words out of my typing hand:xd:

 

[srpntmage]

I am carbon dosing. I am using Red Sea NoPox. It is similar to vinegar or vodka dosing. What I don't get is why it isn't working on my nitrates.

 

[Mike in CT]

I have only used vodka, so we will have to wait till some bio pellet users chime in.

 

[Reefing Madness]

I am carbon dosing. I am using Red Sea NoPox. It is similar to vinegar or vodka dosing. What I don't get is why it isn't working on my nitrates.

Your not using enough if its not coming down.