All about Denitrator

Thanks Waterzoo. So which do you think is most suitable for aros?

Octane - how long it takes to wash the Denitrator unit? It should be quite light, since there are mostly bioballs?

Atom - how do you interpret the ORP readings?

Originally Posted by Spakase

Atom - how do you interpret the ORP readings?

Hmmmm tough question.

IMO,

0 to -50mV - Too little or no anearobe
-50mV to -150mV - limited denitrification
-151 to -199mV - average denitrification
-200 to -280mV - optimum denitrification
-281 to -330mV - anaerobe begins to switch partly to sulphate
-350 and below - optimum hydrogen sulfide production.

Originally Posted by WaterZoo

The first generation doesn't have a ORP probe provison after getting sick of the coil type which needed constant feeding....

This was five years ago.

Originally Posted by atom

You mean Deltec has a coil type denitrator? Strange!

My apologies for not bringing the message clearly.

What I meant was five years ago Deltec sulphur filter doesn't have a provision for ORP probe as I was then exploring for a alternative nitrate filter for my aro tank which was bombarded with about 80ppm of NO3.

This was after abandoning my CIYed coil denitrator as it was a pain in the neck with feeding as well as ensuring constant flow driprate at the output coupled to my regular business trips.

Then opted for the NR1000 which I got initial success in the beginning as I didn't want to purchase the proprietary threaded ORP which the unit is designed for.

However, understand that the threaded attachment is available for standard ORP probe which is good for the users who wants to use their brand of choice for the probe.

Even explored the latest range of Deltec Nitrate Filter but again they needs "feeding" and unless you have a very strict regiment of performing such a task then it is another good option.

But then knowing myself that I will enter into a self denial mode which I felt the best option is to adopt the Schuran Nitrate Filter which needs no feeding.

All sulphur based denitrator do not require any feeding because the feeding is the sulphur itself.

I thought there are two alternatives mentioned by Sunburst, one with siporax, fed with vodka?

Will readings below -350mV be considered important, the lower it is, the worst it has gotten? If it hits -330mV, there is danger to fish life?

Originally Posted by Spakase

I thought there are two alternatives mentioned by Sunburst, one with siporax, fed with vodka?

Will readings below -350mV be considered important, the lower it is, the worst it has gotten? If it hits -330mV, there is danger to fish life?

IMO, using fine pores type media is not very suitable for film anaerobe. Once it get choke (a matter of time), the media will be render quite useless. Very difficult to clean. I was even recommended by the ppl at aquamart to use cerapore but after discussion with Dr Manfred (technical director of AquaMedic) and 1 year of experimenting with different configuration on the denitrator plus studying the designs from other brands like Deltec and Schuran (only the carbon based type), bio-ball is the best follow by extremely coarse sponge/mat.

If the readings on the ORP hits -300mV, bad things are brewing! Some examples:

- Hydrogen Sulfide. Very toxic and bad smell. Bad for humans too!

- Heavy slime. Increase the DOC of tank and lower the oxidising power of the water in the tank.

- Choking and thus reduce or even stop the flow at the output

- Denitrification will be reduce too

- Nitrite and Ammonia might develope.

- Development of pathogens.

From the above, nothing is good for the lives stock.

Originally Posted by Spakase

Thanks Waterzoo. So which do you think is most suitable for aros?

Octane - how long it takes to wash the Denitrator unit? It should be quite light, since there are mostly bioballs?

Atom - how do you interpret the ORP readings?

Personally based on my experience with standard denitrators, carbon-fed, and sulphur denitators, it is based on individual preference.

If you hate feeding then it is best to use methods available in the market other than the Denitrator Filter System.

Originally Posted by atom

All sulphur based denitrator do not require any feeding because the feeding is the sulphur itself.

Bro don't need to keep repeating as who doesn't know that sulphur basd denitrators doesn't need feeding ..

Originally Posted by Spakase

Thanks Waterzoo. So which do you think is most suitable for aros?

Octane - how long it takes to wash the Denitrator unit? It should be quite light, since there are mostly bioballs?

Atom - how do you interpret the ORP readings?

Other than Siporax, you can also use biological media like BioHome Red for the denitrator but you have no option to refrain yourself from feeding. Both of them are very capable media which can provides anaerobic bacteria an extremely large amount of open-pored tunnel structures. Which in turn allows an ideal supply of the anaerobic bacteria with nutrients and a smallest amount of fresh water. With oxygen-poor conditions within the tunnels; this makes the bacteria crack nitrate to get enough oxygen.

Consequently, they continuously break down nitrate, and the aquarium water remains low in nitrate.

Relating to -350mV registers for the Denitrator reactor chamber, the chance of seeing any livestocks in the tank is very very slim and be prepared to do a complete makeover for the tank.

Originally Posted by Sunburst

Relating to -350mV registers for the Denitrator reactor chamber, the chance of seeing any livestocks in the tank is very very slim and be prepared to do a complete makeover for the tank.

I advocate post treatment for all output from all denitrators. I had once subjected the denitrators (x2) to -380 to -420mV for about 2 weeks. All the livestock alive n kicking with no visible change in behaviour. Why? Post treatment. I almost fallen sick due to it!

This is what I do.

- Let the output goes to a protein skimmer
- Use ozone for the air-inlet to protein skimmer
- Filter the output from protein skimmer using wool.

Addtional process; use GAC in FR to remove excess DOC.