Oxydator Questions!

[Claire]

Hi there,
Been trying to find out a bit about these oxydators as they seem like a good way to increase water o2 without gassing off co2. This appeals to me as I have a shrimp tank that I can't gas too high at the moment as they are sensitive to low o2.
The thing is, I can't find a lot of info regarding what you need for it. I have found them here:
Söchting Oxydator - Seahorse Breeder
But there are many different kinds of solutions and catalysts along with it and I'm not really sure what I'd need to get for it as there seems to be nothing eluding to this in the product description.
I also read somewhere about using h2o2 from the chemist for it instead of their own solutions but not really sure how that would work either.
Just if someone could explain a bit, then that would be ideal!
Cheers,
Claire

 

[three-fingers]

Not used one of the oxydators before but seeing as your aim is to maximise both CO2 and O2 in a non-CO2 injected tank the following thread may be an interesting read: http://www.ukaps.org/forum/threads/maxing-co2-in-low-techs.29856/ .

If you are already injecting CO2, then your water is probably saturated or near enough by the middle of the photoperiod .

 

[Claire]

I'm injecting, but I can't saturate as the shrimp don't like the low o2 as a result. So I thought the oxydator would allow me to have "normal" injected co2 levels without the shrimp suffering.

 

[three-fingers]

"Normal" injected CO2 levels of 30ppm are fine for shrimp. Pumping in more CO2 doesn't result in a loss of O2 - quite the opposite, as plants convert the CO2 into O2 - so injecting CO2 results in more O2, meaning the oxydator is not needed for any reason .

 

[dw1305]

Hi all,

"Normal" injected CO2 levels of 30ppm are fine for shrimp. Pumping in more CO2 doesn't result in a loss of O2 - quite the opposite, as plants convert the CO2 into O2 -

I think this true with oxygen levels and I've never used CO2, but I think the problems with high CO2 levels are because the same haemocyanin (the haemoglobin equivalent in Crustaceans) molecules transports both oxygen and CO2. If you have high CO2 levels in the water, the diffusion gradient between the shrimps gills and the tank water is fairly shallow, even if the water is fully saturated with oxygen. If enough CO2 remains bound to the haemocyanin molecules (suspended in the haemolymph), the shrimp will "suffocate" even with 100%DO.

Even though it is a different oxygen carrier, the principles are the same as you get with fish, and I would expect shrimps from cool, flowing water to be less tolerant of high CO2 levels than those from warmer, still water.

Under this arrangement I would expect Crystal Red Shrimps to be less tolerant of high CO2 levels than Cherry Shrimps, and shrimps generally to be similar to the more susceptible fish, mainly because haemocyanin is a less efficient oxygen transporter when compared to haemoglobin.

cheers Darrel

 

[three-fingers]

Interesting, didn't know that haemocyanin transported both O2 and CO2 in shrimp. Although I figured those principles would apply the same as with fish and haemoglobin, this explains why shrimp seem to react faster to CO2 issues!
Though I still don't understand the intended function of the Oxydator:

This appeals to me as I have a shrimp tank that I can't gas too high at the moment as they are sensitive to low o2.

Gassing in CO2 "too high" is obviously bad for livestock but it doesn't lower the O2, it should increase the O2 with photosynthesis. So the Oxydator doesn't allow you to add any more CO2.

I'm injecting, but I can't saturate as the shrimp don't like the low o2 as a result. So I thought the oxydator would allow me to have "normal" injected co2 levels without the shrimp suffering.

Low O2 isn't a result of injecting CO2. The Oxydator adds to O2 levels, but wouldn't allow you to inject in any more CO2 without harming the shrimp. O2 levels should already be high enough in a healthy planted tank with injected CO2, so I wouldn't have thought it worthwhile adding the Oxydator even if you just wanted extra O2 for the sake of it.

The main use for the Oxydator IMO would be in a non-planted, marine or maybe even low-tech tank where the extra O2 might make more of a difference.

 

[Claire]

More my thinking is that with the oxydator, you can add more oxygen without gassing off co2, e.g. by putting in an airstone or increasing surface agitation.

Therefore by most conventional methods of increasing o2, you end up losing co2. Not a direct relationship of co2 pushing out o2, but by needing to have higher o2 through using other methods.

If that makes sense...

 

[three-fingers]

Ah, I do see what you mean.

Tbh I'd think you'd probably lose both O2 and CO2 by adding an airstone during the photoperiod. Increasing surface area doesn't add O2 into the water if the O2 is already at equilibrium level (saturated).

The Oxydator works differently, and from my understanding could potentially allow you supersaturate the water with O2 like we do with CO2 for plant growth. But to what end?

What are you looking to increase the oxygen levels for? If there's something that making you think there's not enough oxygen, maybe its another problem? Or if it's really O2, do you have plant growth problems?

 

[dw1305]

Hi all,

More my thinking is that with the oxydator, you can add more oxygen without gassing off co2, e.g. by putting in an airstone or increasing surface agitation.

Claire that is true, the extra oxygen comes from the break down of the hydrogen peroxide (H2O2). The reaction is 2H2O2 ~catalyst~ 2H20 + O2.

These had a bit of vogue about 20 years ago with Rift Lake Cichlid keepers, there is a description for a DIY one in <Enjoying Cichlids (Revised &amp; Expanded Edition): Amazon.co.uk: Kjell Fohrman, Mary Bailey, Ad Konings: Books>. They work, but I can't really see any advantage to them, in a planted tank with some flow you shouldn't really have oxygen problems, but I'm not a CO2 user.

Cheers Darrel

 

[Claire]

It's mainly for the CRS as they appreciate high oxygen levels to what I've read, and many planted tank keepers are noting an improvement in shrimp growth and overall health using them. From that, I thought one may be worthwhile, but am unsure about the different available concentrations of h2o2 that you get for it and catalyst solution as to what I'd need, and if I could just get chemist h2o2 cheaper (but may need to dilute).