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Hey everyone,

After seeing and reading other people's aquarium logs and having learnt so much from them, I would like to start one of my own.

Situation is I have a 4ft 55G tank with high nitrate problem. Before I took everything apart, the reading registered 40ppm no matter what I do.

The tank was emptied on the 20/04/06 with gravel cleaned and replanted with 3 amazon swords and dozens of thin val.

Installed new Eheim 2215 Canister filter, water turned crystal clear around yesterday. Changed 50% of the water today and installed new media.

Currently running 2 Corse foam, 1 lot eheim substrate, 1 litre seachem Matrix, fine foam in the Eheim.

Supposingly, the Matrix will cultivate anaerobic bacteria that are benificial and will reduce nitrate into Nitrogen gas.

Let's see how it goes.

Interesting JQW,

I never heard of this Matrix product and I have to go to the Seachem website to read up on it after I finish my entry.

... the reading registered 40ppm no matter what I do

I am not sure if I remember that right, but didn't you have a thread somewhere that refered to that problem? In any way, what where the tank conditions then (hardware, substrate, filter, plants, fish, and what not) and what things did you try to do to lower the Nitrates?

Having this information would be helpful (at least for me) to understand where you are coming from.

So far I see one problem with your test of this product - you did all kinds of other things as well. Let's assume your nitrates pan out to be good now, how can you identify what made it that way? It could have been that you had way too much gunk in the gravel, or that your filter was too inefficient, or the new plants help with it, or a combination of all of the changes.

Keep us posted,

Ingo

---

Proud Member of the New Jersey Aquatic Gardeners Club

didn't you have a thread somewhere that refered to that problem

Yes, Little Fish, indeed I had a post regarding to this very problem. But it seems like what ever I do, nitrate level won't fall, and more blue green algae appears. So I thought it's getting real bad, not only the nitrate but other stuff for example excess phosphate etc.

Did a 60% water change, topped up. Repeated again the next day. Nitrate level only dropped a little bit according to both undiluted test and diluted test.

Used to run a JEBO cannister fiter with flow rate 1700lph and only corse foam and fluval biological rings as filter media. Had amazon sword plants moderately planted, 2x36 Watt light for 12 hours daily, daily feeding with frozen food and flakes. Fish are 4 angelfish, 4 platies, 1 dwarf gourami.

you did all kinds of other things as well

Well true. But I thought it's probably more important to monitor how the nitrate level is behaving now, and in long term and weekly nitrate measure. If there is already a high nitrate build up in the tank, and the fish in there are still producing waste which will turn into nitrate eventually, it's hard to get it down anyway. Because it takes time for the anaerobic bacteria to build up, and the speed of nitrate production will inevitably be quicker than the rate of removal. So I thought I'd get rid of everything and try a fresh start, now both aerobic bacteria and anerobic bacteria will cultivate at the same time on the same media, it will at least have some sort of balance to the rate of nitrification and denitrification. In long term, as the population of fish increase, and nitrate level still stays low, I can conclude that the product Matrix is at least working to get rid of nitrate.

The concern I have is that denitrification is not a one step process. It first converts nitrate into nitrite and into nitrogen oxide then into Nitrogen. ie. NO3-->NO2-->NO-->N2 Supposingly if undisturbed in the filter, nitrite will not be released into the water but instead converted into Nitrogen very quickly and then released. The whole process is a reduction process and will only occur if there is organic substance in the water for the anaerobic bacteria to use. Therefore it is suggested that the Matrix media is not to be disturbed for at least 6 month, anaerobic bacteria is highly dangerous and may release lethal chemicals into the aquarium under the wrong condition.

I will try to get further information from my Uni library and people from the department of Botany at my Uni. From my current knowledge about the application of denitrification, it is used in water way management to remove excess nitrate due to excess fertiliser run down into the stream. Hence denitrification from anaerobia bacteria is a viable way to reduce nitrate level in closed water system.


However, regular water changes should not be neglected.


Plenty more to come.

Will keep posting.

Regards,
James

Current tank condition:

55Gal
2x36Watt light at 6500K at 10 hours a day 10am - 8pm
3 Large Amazon Sword plants
Dozens of Thin Val
2 Angelfish
UV-sterlizer 8W
Eheim 2215 cannister filter.
Media: in the order of water flow: EheimMech-->Corse Filter Pad-->EheimSubstrate-->Corse Filter Pad-->1 Litre Seachem Matrix (Good for 400L)-->Fine Filter Wool-->PhosphateSorb (Absorbs phosphate and silicon in water)

Water change at 10% weekly.
ATM:
Ammonia Level: N/A
Nitrite Level: N/A
Nitrate Level: 0ppm

The problem I see is exactly what you mentioned. You cannot disturb the media without messing up the denitrification process. That means you can't clean your filter without removing the media and causing it to start all over. I think I would run both cannisters and use the jebo just for the biological media. Then you won't have to worry about it when you clean your mechanical filtration and it will probably be far more efficient with less trouble for you.

Was a reason ever found for the high nitrates such as tapwater nitrates, an overstocked tank, really messy fish, or not a good enough cleaning routine? If it's anything other than tapwater nitrates then you shouldn't need to rely on such media. Just the correct cleaning/water change schedule and filtration should be enough. Using chemical or filtration media instead of removing the waste is only going to cause more trouble in the long run.

Then you won't have to worry about it when you clean your mechanical filtration

Actually I will still have to put some corse foam in the Eheim canister, to stop junks blocking the bio filter. The designe of Eheim is slightly dodgy, they keep the foam at the very bottom, makes it hard to clean. So even if I have another mechanical filter, I will still need to put foam in the Eheim. I think I will get a prefilter for the eheim instead.

Was a reason ever found for the high nitrates such as tapwater nitrates

Nitrate in water is zero. Still did all my regular maintenance, no over population and no over feeding. It puzzles me a bit too. Heard this product removes nitrate into nitrogen and release into atmosphere, really interested in try out.

Just the correct cleaning/water change schedule and filtration should be enough.

What I am doing at the moment can been seen as an experiment. Engineers use denitrifying bacteria in natural water ways to eliminate high level of nitrate. And the denitrifying bacteria they use is the very anaerobic bacteria that will be cultivated by Matrix. So as an experiment, also for extremely large aquariums where weekly 20% water change is almost impossible or too expensive, bacterial denitrification may potentially be a good solution.

Sunday 30th April 2006

Did a 20% water change on the tank.
Pre water change water parameters are as follow.

Temp: 28 Degrees
pH: 7.20 (Has gone up since Matrix is added)
Ammonia: 0ppm
Nitrite: 0ppm
Nitrate: 0ppm

Im getting similar results using the tetra nitrate minus. I think the deoxygenating nature of the bacterial process does change ph a little.It takes about three weeks to get started and repeated doses to establish itself, but it does seem to work. Bad news is that melafix kills it stone dead though.