Inexpensive Introduction of Oxygen?

[aquaventions]

Stumbled accross this again .... oxygen toxicity is a very real threat. Oxygen can also act as an oxidiser resulting in burns. From a slightly more obscure yet still interesting study, increased levels of dissolved oxygen often does result in slower/lower rates of fish breathing since blood oxygen levels are sufficient but this often causes a build up of other organic wastes since respiration was slowed.

As an aside, when bagging corydoras, eels, bichir, siamese fighters, gouramis, lungfish or any surface breathing species with oxygen for transport, dont deflate ALL the air out of the bag before filling it up with oxygen. The pure oxygen will burn such fish.

I'm interested in the study, could you please provide a link or PM me?

Too much of a good thing is usually a problem, but can anyone tell me how much is too much?

Those who use canister filters along with good surface movement of the water achieve one level of oxygen content. Those who employ a wet/dry filter presumably attain a higher oxygen content. Adding a protein skimmer also increases oxygen content. Introducing ozone further increases oxygen levels.

So my question is what fitration method or methods produces an optimal level of oxygen?

 

[fishdance]

You will need paid subscriptions to aquaculture journals to view most publications and the aquculture industry here in Australia is already difficult enough without people breaking their copyright restrictions. Joining an local aquaculture group near you is a good start if you need local knowledge and expertise.

Also your actually going about this problem the wrong way. To maintain adequate DO levels in the live culture tank, oxygen must be added to the tank at a rate equal to that of the rate of consumption by fish and bacteria. The overall rate of oxygen consumption for a system is the sum of the respiration rate of the fish, the oxygen demand of bacteria breaking down organic wastes and uneaten food (also referred to as Biochemical Oxygen Demand or BOD), and the oxygen demand of nitrifying bacteria in the filter. The amount of oxygen required by the system is largely dictated by the length of time waste solids remain within the system and the biofilter configuration as well as species requirements and stock levels. Temperature, salinity, pH, other gaseous saturation levels will all affect DO. Simply adding DO is not the magic solution although it can utilised in emergencies or manipulated if you understand the dangers. Skimming and ozonation as per your examples are used to remove organic proteins (waste) to optimise DO not to simply increase DO. I hope my brief/blunt explanations are clearish?

The best type of filter will actually depend on your fish species. ie a trickle (wet/dry) may physically introduce the most oxygen but if the fish is messy, a filter which rapidly removes the waste out of the system will easily result in higher DO. If you are after fail safe I suggest you simply reduce stocking levels dramatically for less maintenance and higher safety buffers. If there was one clear best filtration system then thats what all aquarium shops, fish keepers and fish farmers would sell and use.

Using a simple analogy, I suspect your trying to make a high end sport car and promoting this as ideal for everyone. You need to work out whether you want reliability or performance.

 

[aquaventions]

You will need paid subscriptions to aquaculture journals to view most publications and the aquculture industry here in Australia is already difficult enough without people breaking their copyright restrictions. Joining an local aquaculture group near you is a good start if you need local knowledge and expertise.

Also your actually going about this problem the wrong way. To maintain adequate DO levels in the live culture tank, oxygen must be added to the tank at a rate equal to that of the rate of consumption by fish and bacteria. The overall rate of oxygen consumption for a system is the sum of the respiration rate of the fish, the oxygen demand of bacteria breaking down organic wastes and uneaten food (also referred to as Biochemical Oxygen Demand or BOD), and the oxygen demand of nitrifying bacteria in the filter. The amount of oxygen required by the system is largely dictated by the length of time waste solids remain within the system and the biofilter configuration as well as species requirements and stock levels. Temperature, salinity, pH, other gaseous saturation levels will all affect DO. Simply adding DO is not the magic solution although it can utilised in emergencies or manipulated if you understand the dangers. Skimming and ozonation as per your examples are used to remove organic proteins (waste) to optimise DO not to simply increase DO. I hope my brief/blunt explanations are clearish?

The best type of filter will actually depend on your fish species. ie a trickle (wet/dry) may physically introduce the most oxygen but if the fish is messy, a filter which rapidly removes the waste out of the system will easily result in higher DO. If you are after fail safe I suggest you simply reduce stocking levels dramatically for less maintenance and higher safety buffers. If there was one clear best filtration system then thats what all aquarium shops, fish keepers and fish farmers would sell and use.

Using a simple analogy, I suspect your trying to make a high end sport car and promoting this as ideal for everyone. You need to work out whether you want reliability or performance.

Fishdance,

Your explanations are great; however, I think you misunderstand my purpose. Filters work to provide a healthy environment for fish, and this healthy environment can be obtained by different types or combinations of filters. I do not question this. I also realize that adding DO is no substitute for filtration.

There are various indicators of good water quality and corresponding tests to measure them, e.g. pH testing. These water parameters and their measure are a common topic of discussion on aquatic forums. Unfortunately I do not find this level of discussion about DO which is a very important water parameter.

Occassionally I find a reference to minimum oxygen levels for different types of fish, but I have never heard anyone mention what the DO level is in their tank. Should I assume that the minimum DO levels for different type of fish is also the optimal level? If not then I would like to learn what it is quantitatively.

Once I know what that is then I can see how my filtration method(s) measure up against this. My interest in introducing DO arises from my ignorance about whether or not there is a gap between minimum and optimal DO levels achieved through ordinary filtration methods. I have not yet found this information through the Internet even though I have read threads on aquaculture forums.

Assuming the article to which you refer is copyright protected could you please identify it by title, author, publisher, and date and place of publication, and I'll try to track it down while respecting that it's copyrighted?