High nitrate in my 55 gallon tank

butterflyx8i8x

I am having trouble with high nitrates in my tank. I've been doing water changes and the nitrate is still high. There are no ammonia, nitrite, and I have no problem with my PH. I don't overfeed my fishes I have live rocks. Do you know what else I have to do to bring my nitrates back to zero? Or what do I do to stabilize my aquarium?

Lyn

Pasfur

Nitrates in marine aquariums are generally the result of the type of filtration system being used. Please provide more details on your setup so that we can be helpful. What size tank? Livestock? EXACT filtration system? Sand depth? Amount of live rock?

butterflyx8i8x

I have a 55 gallon tank. I have an eshopp sump, CBR bak-pak hang on protien skimmer, coral life uv sterlizer, vortech mp20 pump, 1 1/2" sand depth, 30 lbs of Molokai live rock, Yellow Tang, cleaner wrasse, falco hawk, dwarf eel, 2 butterfly fishes (they are going back to the fish store), 2 clownfish. I did 25% water change today and it still reads high. What am I doing wrong? I NEED HELP PLEASE!!!!

wake49

What is in the eshopp sump? Bioballs and filter floss? Also that CPR Bakpak might not be able to handle your fish load. Not to mention that your sand depth is a little off, as you would prefer 4-6" for denitrification. Or you could do less than one inch, but everything in between is a detritus trap. And I would personally use more Live Rock, as this really helps with denitrification.

Pasfur

If I understand correctly, the eshopp sump is designed for wet/dry filtration. Is this correct? If so, then you have a very simple answer. These sumps are designed to INTENTIONALLY introduce Nitrate into your aquarium. Ammonia is broken down into nitrite, and nitrite into nitrate. The nitrates build up and are removed by water changes. This is a horrible method of filtration if your ultimate goal is to keep nitrates low, which I personally believe should be the goal of every marine aquarium.

My advice is to use a deep sand bed, live rock, and a good quality protein skimmer as your only filtration. The skimmer should be placed in the sump, which receives surface skimmed water that is high in organic waste.

Making this simple change will drastically reduce the problems you are experiencing.

butterflyx8i8x

how big of a water change do I have to to? and how often do i do it? Should I do 25% water change every day or every other day until it goes down? As for my protein skimmer, I cant find something that would wit in my sump because of my return pump is pretty big and it takes up space inside.

butterflyx8i8x

oh yea I also saw my clownfish scratching, I don't see any parasites on them and they also look like they are shaking sometimes. they look healthy but i don't know what do do now.

Pasfur

You have no reason to be concerned about sump space. You have a protein skimmer already hanging on the aquarium. The answer is to remove the biomedia and filter floss from your sump, including the sponge filters.

Now, we have to be careful when this takes place. It is essential that you have enough live rock and proper water movement in the display. Can you post some pictures of the tank?

As far as water changes, the use of water changes to control Nitrates is nearly impossible. A 25% water change will only result in a 25% reduction of the current Nitrate level. Some simple math will show that extremely large water changes are required to maintain Nitrate levels at an acceptable level. The answer is not to change water, but to reduce the introduction of Nitrates to a minimal level, so that the denitrification ability of the live rock is efficient at keeping Nitrates low. The type of filtration is the problem, because you can not allow Nitrates to accumulate at such a rapid pace.

The real purpose of water changes is to replenish trace elements and buffering ions, which are conductive to alkalinity stability. Nitrate reduction does not factor into a conversation about water changes. I would encourage you to look at a recent article written by Dr. Dieter Brockmann, in the Nov/Dec 2009 issue of Coral Magazine. The article discusses water changes, providing more detail on the concepts I've mentioned above.

CORAL - The Reef Aquarium Magazine

butterflyx8i8x

Ok...now what about my fishes? Is the nitrate affecting them is that why my clownfishes are shivering and my dwarf eel is shaking their heads? What do I do now?

Pasfur

Nitrates are not likely to cause behavior changes of this nature. I think you have other things going on, very possibly pH related. Have you tested for alkalinity?