Denitrator?

[motoro]

Anyone here have any experience or thoughts using a denitrator (nitrate filter) on a freshwater tank.  My tank is a little overstocked and I am having a hard time keeping my nitrates low.  And my fish don't react well to large water changes (especially in the summer).  Doing frequent small water changes is becoming a pain, so I am looking for an alternative.  These nitrate filters are a possibility.

Thanks

[fishycanuck]

Is your tank completely cycled? Please give us the parameters of your tank -
-size
-population
-plants
-most recent pH, ammonia, nitrAte, nitrIte, temperature

We can help you better that way.

[bitterman]

I've looked at this and my solution was not what you want a DIY water change system.

I think you best bet will be plants. Artw and I are going to try a test on my 180 to help decrease water changes via my drip system. We are taking a 20 gallon tank that is drilled and hooking it into my sump, from there, it will contain a ton of plants, Lighting will be a 24" 55W CF.  Water will flow slowing through this tank to hopefully use the plants as a nitrate sponge. This is a test (In concept phase right now) and not proven to work yet.

I have seen talk of a small 100-200 foot 1/4" water line with very slow flow, but I have not seen Proof that it is effective enough, or working. This is a link I found for you http://www.aquariumpros.ca/forums/showthread.php?t=18394

How often do you gravel vac? Many people have had this issue as a result of not gravel vacing and wast builds up and rots in the sub straight resulting in high nitrates.

Another possible cause is a trickle filter. When the bio media gets very dirty is can result is high nitrates. Bio balls should be cleaned about 1-2 times a year. I take about 1/2 my media out of the filter and swirl it around in a bucket of tank water from my tank.. Then add them back to the filter. Then a few weeks later do the same things with the bottom 1/2 of my bio media.

What nitrate levels are you trying to maintain? I can't detect nitrates in my 195, 65 setup with a common sump. The 195 has 17 Frontosa, 4 Yellow calvus a syno eruptus, and my 65 has 40 Malawi's, so the bio load on this setup is very high. I only have about a 50% water change per week total, but it is done very gradually using my drip system at 1 GPH automatic water change system.

Bruce

[motoro]

An automatic water change system would be ideal.  However the tank is in a living room and not "very" close to a water source or drain.  This means I would have to run pipes through the ceiling, etc.  That's a bigger job that I want to do.  (for the time being anyway)

The tank is a 220gal with sand substrate.  It is filtered with a couple of canister filters and a couple of HOB filters.  Tanks been up and running for over 5 years. (I am sure its finished cycling) ;-)

Water parameters:

Ammonia = 0
Nitrites = 0
Nitrates = 60-80 ppm  (I am colour blind, so when it gets to the high end of the chart I have trouble telling one from the other.  It may be even higher than 80)
PH = 6.3
temp. = 81F

I change approx. 60% of the water weekly.   And sometimes do an extra 40% water change during the week.

Filters are cleaned regularly.  I don't have a set schedule for them, but only one filter is cleaned at a time.

Tank is stocked with a pair of  P. motoros, a pair of plecos, and some silver dollars.