Hang on filter = Nitrates ??

Ive been having a problem lowering my nitrate levels currently at 20ppm. I do 5 gallon a week water changes using ro water, have a 5 gallon fuge with cheato, and a deep sand bed. I also have a skimmer running in my sump and routinely vacuum the gravel to remove DOCs. I still cannot manage to lower the nitrates. So I was wondering if my hang on filter could possibly be a source of nitrates enventhough I already removed the bio wheels??

 

How often do you change the media in the filter? Also, I would do larger water changes. 5 gallons in a 110 gallon system isnt going to do squat for you. Aim for 10-20% in doing them.

 

I change it about once every 4 weeks but I feel like all it does is hold junk that could cause nitrates

 

about 100 lbs

 

I also have a hang on filter. I don't really have a problem with nitrates, and I don't have a fuge. I change the filter pads once every two weeks and clean them once a week. I also clean it really well 1 a month. I notice that organic solids build up on the pads and at the bottom of the wells. This may be your problem. Also, make sure your RO filter is not old.

 

When I had problems decreasing the nitrates in my 75, I would do 20g water changes every week for a few weeks, then every other week consistantly. You have gone farther than I in getting your fuge going. I went the other route with a denitrator. When I get my fuge in order, I am going to dial down my denitrator so that my Chaeto will still have food but I will not have any residual NO3 to detect. Just an idea.

By the book, it is every four weeks. I disagree with the book. I clean my filter socks every other day. The sponge in my nano I clean at least weekly.

For a reef tank, you are going to want around 150lbs IMO. Base rock is good and cheap(er)

 

I would also clean mechinical media as often as possible. If you can rinse it off everyday-great, I would do that. The point of mechanical filtration is to collect larger detritus, but it turns into bio filtration when people neglect to rinse it off regularly. Thats what you want to avoid. As far as the liverock is concerned, personally, I feel you have enough, esp since you have a DSB which is probably a more effecetive form of denitrification than live rock IF properly maintained. Which would mean NOT stirring it up as commonly thought.
I would also blast the rock w/ a turkey baster when doing W/C to remove trapped detritus from the live rock. I also agree w/ more substantial w/c probably upwards to 20-25% at least until the NO3 is at a more acceptable level for you.
What do you feed your fish and how often?

Good luck