Matrix/De*Nitrate nitrate filter DIY

[Tech Support HK]

It is not uncommon for detritus to build onto Matrix or de*nitrate over time. When this occurs, we suggest placing the media in a bucket of tank water (while performing water change) and rinsing the media gently.

Yes, if enough slime or detritus builds onto Matrix, then the bacteria will not be as efficient at removing ammonia, nitrite, and nitrate. We place filter floss/polyfill in our canister filters in such a way that water first passes through the polyfill and then through Matrix. This way, a large amount of detritus will be filtered from the water before the water flows through Matrix. This is a cheap and easy way to reduce the frequency of biomedia cleanings.

It is also always a good idea to dose the tank with Stability after a large water change, or when cleaning the media. This way, you will be replenishing any bacterial colonies that may have been compromised.

[Abbeysdad]

Just as a point of clarification the siphon inlet tube is positioned in the tank very high such that the filter does not see detritus beyond dissolved organics. What I was reporting on the media was true bio-slime, the byproduct of biological filtration. It seemed to be fairly significant for the approximate 3 weeks the filter had been running. In part this may be due to the slow water flow through the filter as I would expect a faster flow would have a cleansing effect. I will monitor and perhaps tear down monthly.

Thanks,
-Mike

[Tech Support AN]

Ah, thanks for the clarification, Mike!

I would agree that the faster water flow may act as somewhat of a cleaner through the media.

[Abbeysdad]

I guess the bigger question is if the bio-film/bio-slime does in fact inhibit the function of Matrix/De*Nitrate or is it merely a pseudo 'matrix' of the bacteria itself? Assuming that the water is pre-filtered before the media preventing detritus, does the media really require any periodic cleaning or would it be better instead to leave it undisturbed?
(This is a similar question to that of a substrate in a tank with schools of thought suggesting that the beneficial biology is in layers and disturbing those layers in counter productive).
Thoughts?

[Tech Support AN]

The Matrix is what provides the "home" for the beneficial bacteria, inside and out, of the media. So even if you were to rinse it from time to time, the internal pores that houses the anaerobic bacteria will not be disturbed. However, just as a point of reference; on one of our 265 gallon SPS tanks here at the office, we have had Pond Matrix submerged in the sump for 10 years now, without ever touching it, and the nitrates are negligible. So I can say with certainty, that if left undisturbed, they still function properly.

[Abbeysdad]

Interesting, but what is the water flow rate through the sump with the pond Matrix?

[Tech Support AN]

800-1000 GPH. It might be that you do not have enough flow going through the media. Just a thought.

[Abbeysdad]

[QUOTE=Tech Support AN;10231]800-1000 GPH. It might be that you do not have enough flow going through the media. Just a thought.[/QUOTE]

Early on, you folks told me with my DIY canister of 2 liters each of Matrix and De*Nitrate with a flow rate of 3.5 gph using the Tom Aqua Lifter pump that it should work well. I later questioned if I should have a greater flow rate (in this very thread) and was told again that the current setup should work well and using Stability, I should see nitrate reduction in a couple of weeks.
When I recently reported that I reduced the flow to O2 starve the canisters to aid in anaerobic development after two months because there was no nitrate reduction, you folks said that was a good idea.
Now you suggest that maybe I don't have enough flow? Hmm "What we have here is a failure to communicate."

[Tech Support AN]

I'm sorry that you feel we have failed to communicate properly with you. We are simply trying to troubleshoot the issue and come to a resolution. In all honesty, the Matrix/de*nitrate should function properly under the lower flow rate. As long as the media is receiving water flow through it, it should allow for denitrification to occur. Something just doesn't seem right here, so I thought maybe we could try a different route to see if we get positive results. Not every tank will respond the same, so sometimes it is necessary to change up methods and go about it differently.

My recommendation would be to increase your flow rate to see if anything changes. Again, we are sorry that the original plan did not work, but hopefully with a few tweaks, we can move in a positive direction.

[Abbeysdad]

I appreciate the help and having done a lot of tech support, I realize that once the obvious solutions are exhausted, it's time to reach for other things to try. (sometimes you need a bigger hammer <g>)
Unfortunately, in this setup, the Tom will only handle 3.5gph. Perhaps that just isn't enough flow/pressure to penetrate the media. On the other hand, the canister is packed with media so considering the displacement, there's probably only 4 cups of water in there at any given time.
The more I think of it, the bio-slime surface coating is natural as even rocks in fast flowing river are coated with bio-slime.

I tore the filter down, rinsed the media and have the flow valve turned back up to max 3.5~pgh. I'll just let it run and see if we can get this thing to mature. Having finished my second 250ml bottle, I'm all out of Stability now so I'll have to get some the next time I'm near the pet store.

Thanks,
-Mike