Importance of oxygen in the water

[jim barry]

i think the air is very important and ive said many times that when my rays dont eat as well as usual the first think i look to is the air pumps / air outlets being blocked. i clear the outlets and the rays are fine again.
its possible that the rays have been breathing heavy for a long time and it was just considered normal in that tank but then when the pump went out that was a straw too much and affected the system too much (probably affecting bacteria too).
did the guy even have a sump ? i doubt this would be much of a problem on tanks with sumps. i have one heavily stocked tank with a sump and i dont worry about the o2 too much there but a much larger tank i have regularly gets the air pump outlets blocked and i notice it there ( they are cleaned at least once a week to clear potentialy blockages ncidently however they still happen due to the location).

i would be interested to know more though just so that i can hopefully learn something. if anyone has a link i would be interested.

The post was on FB mate, not sure if he would want to share his missfortunes. Having said that there was very little detail in the post. Just stated he had got up to a tank full of dead fish due to an air pump, thats it. No other detail, hence me starting this thread.

 

[jim barry]

this is one of the arguments on why K1 needs so much air



I absolutely agree. I think a lot of our unexplained losses are due to oxygen. I definitely do not think we give it enough thought. Oxygen levels fluctuate and short stints at low levels can kill lots of fish.
Hope this is not against the rules but here are some informative reads written by hobbyist on the topic
http://www.planetcatfish.com/shanesworld/shanesworld.php?article_id=313

http://plecoplanet.com/?page_id=829

Very interesting read, thank you Charney!

 

[davenmandy]

Something to chew on, my rays were in totes for over 12 hours during the move from one house to another. Total move took 16 hours, so sometime between 12 and 14 I'd say I got them back into the tank, but the full tank wasn't running until 16 hours. They were individual in the totes, each had a bubbler with an air stone in the tote. Really didn't see much in terms of stress and such, they bounced back immediately, no issue. Not sure if this helps, maybe this means the tank turning over with the pump is not as important as keeping a bubbler going? Idk. But I imagine a 16 hour power failure in a big tank wouldn't be as devastating as them being in totes as there is more water to dilute the waste, so is the trick to make sure the bubbler is going? Possibly, would make our failsafe systems a bit less costly if that is mostly what we had to worry about, and maybe keeping the water warm.

 

[Jesseliu13]

If he had a fluidized bed media, is it possible the bacteria in the media used up all the oxygen faster than it could be replenished through gas exchange?

this is an interesting notion... i 2 sources of air currently on my bd pup tank... It runs a 1744 gph air pump for the k1 chamber and a random cheap air pump for the tank... i was contemplating on removing it as it looks as if my tank is cloudy with air bubbles lol. now im not so sure. after reading this im going to forget making it a display tank and removing the bubbles. i'll keep my bubbles in now lol

 

[keepinfish]

Wonder if this would have happened with a UV sterilizer working at level 2 sterilization??? I've always been told that one of the biggest benefits of UV is more O2 in the system since the UV is nuking all the little stuff that can rob a system of O2.

I've always been a firm believer in over killing the air. On my big system I run a pondmaster AP100 on my filtration (and use it all) then use a Jehmco 60 just for the diffusers in the tank...... I think it pencils out to over 200 lpm. Then 220 watts of UV on top of that.

I've always wondered why I don't see venturis used more on tank returns. For what they cost, and what they do, it seems kinda silly not to be running them on tank returns..........

i totally agree with the uv helping oxygenation! Im glad i went with it, and will not go without again..

One time i had an issue years ago when i first got an acrylic tank. I filled it to high and there was no surface area, the water was to the top. i could not figure out while everything was gasping for air.
Something to keep an eye on as well.

 

[spotfin]

Does anyone actually measure the DO level in your tank? It would be interesting to monitor the levels over a few days and record in the am vs. pm, with air on (if you use supplemental air) and air off, and turn your pumps off for a while and see how quickly the DO drops.

 

[DB junkie]

I've asked before about monitoring D.O. and came up with about the same answer as monitoring conductivity and that answer was......... {crickets chirping}

lol.

If I remember correctly monitoring D.O. is NOT cheap.......

 

[Thekid]

I believe BrookKeeper monitored DO as part of his thesis project.

 

[skjl47]

Hello; Someone please fact check my following comments. From the dim past I seem to recall a term "partial pressures" with regard to gases. Sort of something like this, O2 is around 21% (percent) in the atmosphere around us. Aggitation with bubblers or other mechanical devices cannot raise the oxy levels in water to more than the 21%, no matter how many we use.

Ther is also something about the rate that gases will dissolve in water. I did run tanks with no bubblers or filtration at all in the dim past. Gas exchange thru the water surface only. This may be one reason I still favor the longer and wider tanks over the tall tanks. The bubblers and other aggitation make it more likely for the maximum oxy percentage (21%) to be present in tank water. A big improvement over the gas exchange thru the water surface only.

The only sure way I know to not have problems when the power goes out or a filtration system fails is to lightly stock a tank. Meaning stock only to the level that surface gas exchange will work at. The battery air pumps can save a tank if you are around and aware. Light feeding so that there is less excess food around can help prevent the decay process from taking up the O2. Cooler water also will hold more O2. Live plants can make O2 in the presence of light, but can use O2 during the dark.