can't get the nitrates down

nemo79 · 03-04-2007, 08:21 AM

Hello everyone,

Well after all the water changes, vacuuming the substrate, blowing my rocks, I have been unable to lower the nitrates beyond 20, I have even installed kents nitrate sponge and no change after a week. I have stopped supplementing zooplex and phytoplex and I only feed a tiny amount every other day. I am at a loss as to what to do now.

I am now fighting some brown algae that appears on the front glass of my tank.

Tangster · 03-04-2007, 08:26 AM

A good skimmer and a denitrater coil or box is what you need problem solved the nitrate is the last link in the aerobic chain and you have nothing to consume them on the anaerobic side to finish the job.. Or you can add several inches f sand to your tank and make it a DSB or add a rfugium or algae scrubber you have to find someway to get these used as a food source by somthing else.

nemo79 · 03-04-2007, 08:34 AM

How do I build a denitrator and what is this box, I've never heard of it before? I am willing to try anything at this point. How do you run the denitrator?

Tangster · 03-04-2007, 09:03 AM

Look for a NITREX DENITRATER BOX ?? I think its called to use a coil you need a sump. I also think they sell the media that is pre soaked with the Alcohol /sugar to keep the box fed ? I have never used one by these people but know of several that did and it did a good job.. I used to make mine from black acrylic and fed it Gin or vodka to keep it going Nitra-Gon used to make a coil if they still do now or not ?? I use the coils myself now But you need a sump for that..

RAVEN · 03-04-2007, 03:13 PM

Here's a few things you can try to help. Feed sparingly, every 2-3 days. Are you using flake or pellet food? These foods are extremely high in protein which is the root of ammonia and nitrates in fish waste. Stick with frozen foods for a while.. You have alot of fish in that size reef tank. Clean out you Aquaclear filter if you already havent and remove the sponge.
Clean out the Remora skimmer with a hose to remove any sludge from the bottom. You can also increase its skimming ability by switching to a Rio 1400plus pump(425gph) or a Via Aqua 1300 (375gph) vs 295 for the MJ1200.
Then do a couple of 40% water changes in a row.

There is also an oxidyzing product from kent marine called poly-ox that Ive used in the past. It oxidyzes sludge so it cant be broken down into nitrates. It worked well for me. I slacked off on tank maintenece for a while and used this product with good results.

Also, you can try Sea chems Purigen resin which absorbs organics. A company called Magnavore makes a nitrate absorbing resin as well.
Magnavore Company, LLC
I use their phosphate absorber and it works great.

The big thing is to find the root of the problem and do routine water changes and tank maintenence.

G-Boy · 03-06-2007, 10:25 PM

Nemo, 20 is nothing to loose sleep over by any means. Actually, with what you have in your tank, you prob are at the lowest level your ever gonna be at. The only thing I see missing that could help if you do over feed once in a while would be about 30 more blue hermits. I feed less then 1/4 cube of frozen food every other day along with a touch of phyto and zoo. I stay at around 10 with only 2 fish. If everything is looking good and healthy and your readings dont get any higher, enjoy! Just my opinion.

rayjay · 03-07-2007, 07:48 AM

Personally I think too many people spend too much time and money to fix algae problems that are going to happen anyway in the first year to year and a half.
Years ago, no one that I can remember ever got upset about a nitrate reading of 20. I don't even consider nitrate to be worth testing for as I never found it to be a problem when I started up 13 yrs ago, and have never tested for it in any of my tanks since.
You have too many fish though for that size of a tank and especially with such a small amount of live rock, even though you have a sand bed I believe.
The live rock is the main nitrate eliminator in my tanks and I go with a minimum of 1 1/2 lbs of QUALITY live rock per gal of water.
If some of the rock is dense or considered to be base rock, then you need even more rock in terms of weight because the denser the rock, the less porous it is to be able to harbour the nitrifying bacteria. (although the nitrate stages occur in the dense core of the rock in the anaerobic zones)
People spend a lot of money to get rid of nitrates when MANY times, all that they have to do is use that money to buy more QUALITY live rock. (the lighter the better)
You have spent a lot of money so far in this hobby, have nice lighting system for the tank, but don't have the core of the tank to be as successful as you might otherwise be.
Search out pictures of long term set-ups on the various forms in the Tank of the Month sections, and see just how many excellent tanks have only a little live rock. They would be the exception, not the norm.
Another thing to consider is removing everything from your mechanical filters as was previously mentioned and just use it for water flow/surface agitation for the air/water exchange of gases.
If there is foam or other filter material, (even the carbon if you use it continually) it provides area for the nitrification process up to but not including the nitrate stage. Therefore, this produces nitrates that you don't have enough live rock to process them.
If you feel the need to use carbon, use it only about 1 week a month at most.

coral reefer · 03-07-2007, 09:12 AM

Try using vinegar, calcium gluconate or glucose to add dissolved carbon to your water! This carbon source will promote denitrification in your live rock and sand lowering your nitrate level!! Carbon sources will also increase your calcium and alkalinity levels!
Dosing kalk with vinegar, for instance will help to increase the amount of calcium concentration in your solution by roughly 9% more than by using kalk alone! Plus it lowers your pH of your kalk solution/and your water possibly, becuase kalk has a pH of 12!

rayjay · 03-07-2007, 10:11 AM

I've never added carbon sources to my tanks so I have no direct experience with it myself.
However, Randy Holmes-Farley has commented negatively about it in a thread on his forum.
I forget all the negatives about it but one is bacteria growth that can occur as carbon sources are food for bacteria growth.
I'm not sure but does this mean that cyano, which is bacteria growth has the potential to feed off the carbon source as well?
Anyway, I know enough people have had success with various carbon source additions to know it works sometimes, but based on Randy's feelings I would respectfully decline to use them on my own tanks, as his knowledge is much greater than most in this hobby, at least with water chemistry in mind.
Unfortunately, Randy has retired from his RC forum as of Monday last so we won't benefit from any more of his comments.

nemo79 · 03-07-2007, 10:27 AM

Thank you all so much for all the info. The one thing that concerns me with my nitrates is the algae. I have brown algae that appears and I just saw a small amount of a green algae on one piece of tufa, it's dark green and has a slimy look to it. Not sure what this is but I want it out before it spreads. I have started to do water changes weekly now due to my bioload. I am going to p/u live rock on the weekend but I can't seem to get any premium LR in my area, it's all crap (excuse the french) so I have to cycle it. I have very large pieces of LR in my tank which weighed about 5-7lbs each when I bought them, so I am not sure if this is good or bad and then I used 20 lbs tufa for the base, which the LR sits on with lots of openings for flow.

The only thing in my filter is carbon and the nitrate sponge. I want to get rid of the tang to lower the load but I am worried about catching it? It really sucks not having a car to get to better shops in the area where I could get cured LR. Well for right now I am going to continue with weekly water changes, minimal feeding every other day, and I am running my lights for only 7hrs to reduce algae buildup. thank so much everyone.