Filters and Oxygen Starvation

[caudelfin]

I am not sure how to word this but I will try. To me all of the power filters, canisters, UGF's operate only on the oxygen in the water, except the one with the bioconverter wheels (and they are another story), and there is not enough oxygen in the water to properly provide bio conversion. That is not quite right, I mean here that the oxygen used in conversion removes some oxygen that could be used to increase your fish load and more material must be used to perform the bioconversion than if more oxygen was readily available, if you follow my drift and I am somewhat drifty here But water does only have so much oxygen available and that limits what we can do.

I prefer the words bio converter to bio filters as the biofilter does not really filter anything, it does convert different forms of nitrogen to one the the fish can live with unless it gets too high through the lack of water changes (nitrate). Thus most filters are really oxygen starved. That is why marine folks use wet and dry filtration, the bioconverter is covered with water and removes the ammonia and nitrite from the water and then the water is removed and oxygen is supplied to the bioconverter material. One filter, the Eheim Professional Wet and Dry, does provide good oxygen flow to the converter. It is too expensive for me.

And plants solve nothing, in that during the day they give off oxygen to the tank and you need to add carbon dioxide for the plant as it needs carbon dioxide while it gives off oxygen. BUT at night the plants take in more oxygen than given off during the day. So actually they take oxygen from the aquarium and the fish there in over a 24 hour period. There is now a power filter that also provides wet and dry circulation to the bio converter, it is the Tetra and with it you have the opportunity to fit the Tetra Capsule heater in to this filter. They claim it does away with many heater problems and hot and cold areas, but it seems to me that the water at the output of the filter would be warmer than the parts of the tank some distance from the filter, but you would not have fish who do not like the heater intruding into the tank and fight with it until it breaks. I actually had this happen. Nothing bad happened to the tank but it did lose the heater and the water was getting on the cool side when I discovered it.

So maybe that is a good idea to place the heater inside the power filter. I just don't like the noise of the power filters. I use Emperor 400's, a Marineland H.O.T. tank canister and UGF in another tank. The UGF has been the best of all filters as far as not losing fish in that tank, but it requires a constant vacuuming and it has other problems also. So I have removed it and am cleaning my 90 gal tank which is temporarily out of service. I am thinking of adding a canister, the FilStar XP3 to the 90 gallon tank, it is the right price at the moment, less than $100 at one catalog place and it seems to be everything one would want in a canister.

My question is to stop the removal of oxygen from the water by the ceramic rings bio converter section, would it be possible by using an air pump to insert the out put into the filter uptake adding oxygen to the water and ceramic rings OR would the cause an air block or lock in the canister and stop its operation, possibly burning up the pump motor also?
Any ideas??
Caudelfin

[mr86mister]

hmmmm

Just like in nature, O2 gets into the water through the surface area of the water. All your filter needs to do to help things is break up the surface area a little to allow for even more O2 to enter.

[melonie]

I happen to agree with your theory to some degree. When trying to get biological conversion in the anerobic chambers of sealed canister filters, indeed all the oxygen for the bacteria reaction must be pumped in with the tank water. In discussions about this matter on a different website, the general concensus was that it's primarily a matter of relative quantities, or just how large of a bacteria colony is trying to extract oxygen from just how much water. The concensus was that in certain high density applications like Fluidized Bed filters it might be possible to deplete the oxygen dissolved in the water, but that in ordinary density applications if there is enough dissolved O2 to keep the fish from being distressed there is also enough dissolved O2 to supply the bacteria colony. Also, this is a much smaller issue with fresh water than with salt water due to the dissolved O2 coefficient. At any rate, I agree with you totally on the virtues of bio-wheels and wet/dry filters which have direct access to atmospheric O2.

[caudelfin]

Well, maybe. But in nature there is almost no fish load to the amount of water available. Aquariums, I feel, are different, as we tend to stuff in as many fish as we can. This is not like nature. All the fish use oxygen. All the things I have read about this situation is IF we must remove our fish load to the same amount as nature contains in the natural waters whether it be rivers, lakes or sea. We would only have on small fish in a 90 gallon tank perhaps none.

Actually oxygen starvation is worthy of consideration. The bacteria converter also uses oxygen, if only a small amount of oxygen is available for this then only a small amount of ammonia can be converted and that spells trouble.

Crowded aquariums are not like nature. We need to take all the recommended steps to keep our tanks well aerated and plenty of oxygen available. I read a very good article the other day on this subject. If I can locate it again, I will put the address under this area.

But the main question was: will forcing air from an air pump up the intake of a canister cause the filter to stop functioning?
Caudelfin
and yes I do know that caudal fin is the correct spelling but I have a friend who uses that name so I changed it up slightly.

[krap101]

i think that the surface agitation should be enough. because if theres too much carbon dioxide in the water it'll just get diffused into the air

Originally Posted by krap101

i think that the surface agitation should be enough. because if theres too much carbon dioxide in the water it'll just get diffused into the air

Obviously Krap101 and I are right, or we would all have tanks with a bunch of dead fish.

[krap101]

or maybe our fish are turning into c02 breathing monsters

[Jchillin]

One method of getting additional O2 is the addition of a bubble wand. While most folks think of them only as decorative, they do supply surface agitation as well as provide something nice to look at.

When I set up my canister filter and sealed it up, the first thing I thought of was how much O2 can get into this closed environment and provide enough O2 for both the beneficial bacteria and the inhabitants. The outflow does this through the surface agitation...and the process starts all over again. The question is "How much O2 is getting into the canister?" Can it be measured. We know that some is getting in or the bacterial colonies would die off regularily, thus causing mini-cycles.

In regard to plants...plants give off O2...they don't use it. I have never heard that they do. Since a lot of CO2 is diffused into the air, the plants will not have enough and die off. Low light plants do not require CO2 dosing.

[krap101]

but when the water hits the water (spray bar) the c02 is diffusing and the oxygen is getting back into the water

back to the c02 thing. there is always some c02 present everywhere. because without c02, in a sense, we die. #1 no co2 means where not getting oxygen #2 no c02 means that plants cant put out oxygen.

Originally Posted by caudelfin

And plants solve nothing, in that during the day they give off oxygen to the tank and you need to add carbon dioxide for the plant as it needs carbon dioxide while it gives off oxygen. BUT at night the plants take in more oxygen than given off during the day. So actually they take oxygen from the aquarium and the fish there in over a 24 hour period.
Caudelfin

This portion of your post has been edited, it is in violation of the User Agreement. Further violations of the User Agreement could result in removal from our community., photosynthesis is a ONE-WAY reaction, plants never take in O2 and give off CO2.

[czcz]

This portion of your post has been edited, it is in violation of the User Agreement. Further violations of the User Agreement could result in removal from our community.

Dude, thats completely unnecessary. Relax. As I understand, plants like any living thing respire, taking in O2 and giving off CO2. I think the net result over 24 hours (with 12 hour photo period) favors O2 though.

Fin,
You may want to read George Booth's articles, as he's measured close to O2 saturation in planted tank systems. I think planted systems are indeed your answer, since it not only saturates the water with oxygen but also gives you nitrate uptake (eliminating the need for anerobic filtration as mentioned earlier). Hard to compare aquariums to nature when the tank isnt planted.

Introducing O2 from air pump into the canister intake may break the impeller.

HTH

Originally Posted by czcz

Dude, thats completely unnecessary. Relax. As I understand, plants like any living thing respire, taking in O2 and giving off CO2. I think the net result over 24 hours (with 12 hour photo period) favors O2 though.

Fin,
You may want to read George Booth's articles, as he's measured close to O2 saturation in planted tank systems. I think planted systems are indeed your answer, since it not only saturates the water with oxygen but also gives you nitrate uptake (eliminating the need for anerobic filtration as mentioned earlier). Hard to compare aquariums to nature when the tank isnt planted.

Introducing O2 from air pump into the canister intake may break the impeller.

HTH

I stand corrected czcz. However, you are also right that plant respiration is far overshadowed by the amount of O2 they put into the tank. Basically, plants will aid in your O2 levels, not detract from them as the poster said. Geez this board is touchy

Originally Posted by Tony Starks

This portion of your post has been edited, it is in violation of the User Agreement. Further violations of the User Agreement could result in removal from our community., photosynthesis is a ONE-WAY reaction, plants never take in O2 and give off CO2.

Is this a new policy? Less than two weeks ago a user was saying that I was an idiot and that I was a big loser because I spent a lot of time on the boards and no one edited his posts, they just locked the thread so everyone could read it but I couldn't respond

[melonie]

But the main question was: will forcing air from an air pump up the intake of a canister cause the filter to stop functioning?

Assuming that the canister filter has its pump located at the top of the canister, and is operating in a 'suction' mode, then yes, injecting air up the pump intake hose is probably going to lead to pump cavitation and/or airlocking (i.e. loss of 'prime'). As to doing any actual physical harm to the pump or filter, probably not.

One method of getting additional O2 is the addition of a bubble wand. While most folks think of them only as decorative, they do supply surface agitation

true, I run a bubble wand for this reason, and they also effectively increase the air to water contact area of a given size tank by adding the net surface area of all of the air bubbles to the tank's top surface area.

Caudelfin, my own easy answer is to run two 'smaller' filters -- one of the canister/modular style for the best mechanical and chemical filtration, and another HOB style filter with a bio-wheel so that the bacteria 'conversion' reaction has access to all of the atmospheric O2 it needs.

[malkore]

Please keep this thread on topic, and refrain from derogatory remarks.

[greenmaji]

I think the problem here is that he wants to have plants and plenty of O2 for his filter.. All I can say to that is there is plenty of dissolved O2 for the filter, fish, and plants at night. But Ive read elsewhere that people have had O2 problems during the night with constant CO2 injection.. in that case putting a airpump on a timer for lights out will fix that problem..

[greenmaji]

Originally Posted by czcz

As I understand, plants like any living thing respire, taking in O2 and giving off CO2. I think the net result over 24 hours (with 12 hour photo period) favors O2 though.

The net result is more O2 czcz..

[bzbee]

yes, injecting air up the pump intake hose is probably going to lead to pump cavitation and/or airlocking (i.e. loss of 'prime'). As to doing any actual physical harm to the pump or filter, probably not.

I'd imagine this to be the equivalent of running the impeller dry, which I've always thought leads to overheating and eventual failure in a matter of hours? Or am I being paranoid?

[greenmaji]

I have had impellers dry for days.. didnt hurt a thing... just my experience though.. I still dont see the point of adding O2 to the line because there is plenty of O2 in the water already.. just not as much as you might like.. thats what a wet/dry is for.. unless you want plants then the plants will add the O2..