UGF responsible for high nitrates?

The first time I did it was when I had to move my tank. And I figured while I have the thing torn apart, might as well give it a good cleaning... And you are absolutely right, it was scary. I could barely see any glass on the bottom because it was covered with @#$%. I mean it was BAD. That's why I thought that might be your source. If you mean by bad for the fish, you mean with hurting the cycle, all you have to do is when you are emptying the tank, keep anywhere from 25-50% of the old aquarium water and put the gravel in that water, don't wash it. then you can clean your tank, and put the wet, uncleaned rocks back in, add the old aquarium water, then add new water. Any spikes should be minimal, in essence, because the gravel remains in the actual aquarium water, it is like doing a 50% water change. If you want to minimize spikes even more, keep more of the old water. It's a lot of work, but it might be worth a try. But mine was only a 10 gal so it made it a lot easier....
 
Personally I have no issue with UGF, or now RFUGF. I can maintain the same nitrate levels with these filters as with any other filter in FO tanks.

In this case I would suspect improper gravel selection and insufficient maintenance - both water changes and vacuuming.

Strongly agree with wetmanNY's post above - very good concept.
 
That dark brown floc that collects under the UGF plate is humus. It's organic matter that has done almost all of the decaying it's capable of. It's not rotten and it's not rotting. It should have had the rich earthy clean smell of leafmold, or wellmade compost-- for that's what it is: compost. Humus has given back almost all the nitrogen of the organic molecules that originally made it. Humus is what makes a dark loam black and fertile. It has many sites that trap and hold phosphate and heavy metals.

Humus is not gunk, junk or garbage. Humus is what's missing in a raw new "aquarium" gravel substrate that goes along with algae and green water in a new system.

* * *

I didn't mention in my first post that there are other forms of nitrogen-- aside from ammonia-- that do enter our systems: food for example.

And I didn't mention the nitrates that may occur in some tapwater, especially in heavy agribusiness regions.
 
Thanks for the feedback WetManNY. But still, I did not fully understand your opinion about this one: do you think I should remove this substance (and in which way), or better leave it alone as is?
 
Test your tap water!
I knew I had nitrates in my water before I moved into my house. I had the water tested for drinking purposes and was not into fish at the time. So, after about a year and a half, the back of my memory whispers, "Hey, you should finally test the nitrates yourself because you keep oscars now and maybe that's why you are constantly battling HITH."
I finally tested it myself with the fish tests and I have a reading of 12.5 naturally. That's quite a bit to start with! So, you should go ahead and test so you know what you're starting with too.
 
Originally posted by BillyHal
(and in which way)

I use a UGF and never had bad nitrate problems... but I also figured there was a finite amount of space under that plate. My plate is such that it is not an open hole at the base of the riser tubes so I couldn't insert tubing down under. There is a gravel vacuum the same diameter (second smallest at Wal-Mart and cheap, too). The vacuum cap fits over the UGF riser tube, I start my suction, and drain 25%. It's not just the under-plate water that gets sucked, I realize, but I do this about once every 4 months or so.
 
AquariaCentral.com