Too Much Oxygen?

[kramers]

Ok, silly question. Is it possible to over-oxygenate to the point of having slightly cloudy water? Right now in my 55g, I've got 2 Tetra Whisper 60 air pumps, only 1 being used right now with a 35-40" bubble wand which is producing very fine bubbles. When I first noticed the cloudiness, I was using both pumps and the wand was under the intake tubes of my HOB's ( 2 BIO-wheel 350's).Since then, I've turned off one air pump and moved the wand up higher above the intakes to prevent cavitation of my filters and have used clarifiers. It's cleared up quite a bit since then but there is still a slight haze to the clarity and it doesn't seem to be affecting anyone in the tank.

 

[riverman444]

How long has your tank been set up?

Do you use CO2 or have live plants?

Is your tank close to a window?

 

[kramers]

All of my plants are fake, kept having them get eaten or all out destroyed. I don't use any CO2. Yes it is near a window with a dark backdrop since Aug '05 when I got the tank.

 

[Teelie]

It is possible to over oxygenate the tank and cause problems, including killing the fish. I can't remember the exact term but it's something like hyper-oxygenation. If you have a good filter running, you shouldn't need any other kind of oxygenator.

 

[Trance2006]

I had one wood airstone in my tank. I run in 24/7 usually I take the air level way down during the night and when I am at school, but reurn it normal when I am home. And when I say turned down I mean a small tiny stream of air. IS that ok?

 

[Dorkhedeos]

i dont think this is even possible. the cloudiness isnt from the oxygen. water that is left standing already has as much oxygen it can hold. aerating this only speeds up gas exhange, it doesnt add more oxygen than there is in the air into the water. unless the air in your house is pure oxygen, i dont think you can over oxygenate the tank

 

[Teelie]

It's quite possible. When the water reaches a certain saturation level, it becomes dangerous to the fish. It's kind of like inhaling too much air at once, you get light headed and can pass out, only prolonged exposure can kill. I'm trying to find the article(s) on it but it's taking some time.

 

[kramers]

Going by what Trance said, I had thought about turning off the pump for a few hours each day, just to see what happens ,although I don't think this will solve the problem. But, nonetheless I'm open to any and all suggestions. Thanks

 

[Bignose]

By what I have read, an O2 saturation over 125% is deadly for fish. However, without some very rare occurrences, this is very unlikely to happen in a home aquarium.

The most likely way to get over 100% saturation is to take cold saturated water and heat it up very quickly. The cold water can dissolve more gas than the hot water, so when it is heated, the water can be over saturated. However, over 100% saturation is obviously unstable, so the system will be moving back towards 100% -- meaning that over saturated water will always be out gassing the extra oxygen.

With bubbles and filter returns, the gas exchange is very quick. And, I really don't think that aquarium heaters could heat the water up fast enough for more than a few % oversaturation to occur. Often when this occurs, anyway, bubbles start to appear all over all the surfaces of the tank. This is really bad since a bubble could form on the fish's gills, effectively suffocating it. This is another great reason why when you put in new water it should be about the same temperature as the tank water.

 

[Teelie]

Possibly a tragic example that over saturation can happen even in normal conditions. Since you have to register to read the thread, I'll requote it here:

This has been one of the worst days of my life....

My hubby is in Atlanta for business...so taking care of the fish falls to me...no big deal...I've done it before...
Fed them last night...everyone was fine...everyone ate....everything looked normal.
Got home late from work after dealing with a different disaster....grabbed a quick bite and headed off to a hockey game. Got home at around 9:30 and I knew something was wrong as soon as I got in the house. It smelled 'fishy'....
So I ran downstairs...and saw the absolute worst sight I could ever imagine...

ALL FISH ARE FLOATING....
Pump and filters are running okay, but tank is hazy...and looks totally lifeless. All Africans are floating at the top....four full grown tin-foil barbs, syno cats....all the clown loaches...I see the huge Tilapia face down in the front corner...and under him the marble cat. And...then to my horror...I see our Pacu in the back corner....he's not moving...
I quickly call my husband and thank goodness I can reach him....he walks me through backwashing the filters and doing a big water change. I'm shaking so hard I can hardly function. All I can think is "NOOOOOO! this cannot be happening!" I get the water out...and start refilling and now comes the time when I have to start trying to get out all the bodies...
By now I can see that BOTH Irridescent Sharks are swimming around like it's just a regular day...they seem to be unaffected. There's 2 or 3 dozen African fry schooling around...and I've seen 4 of the 6 plecos. The Pacu remains motionless...and I can't even locate the Arrowana.
I start scooping out the fish I can reach...and have to accept the fact that the Pacu is dead....and I can't reach him to get him out of the tank. By now, it's 1:00 am...and I am at my wit's end...I'm trying to reach a friend who owns a LFS here that we've known for about 20 years...I finally get hold of one of his employees and he THINKS he may still be down at the petstore. So..I race over to the store, and he's there! But the door is locked and he's in the back room....so I hammer on the front window until he hears me. I tell him what's happened and he follows me home.
I'm so thankful for his help...he takes over and tries to get the remaining fish out...the Pacu is the hardest...he's in the corner and is at least 40 pounds...but we finally get him out...
Those of you who know me...know how I feel about touching fish and fish water...but I did pet him one last time...he would have been 28 this year, and is like our kid....gah...I'm crying so hard I can barely see the keys to type this. I just can't believe he's gone.
We tested the water and everything is normal...Ammonia = 0 Nitrites = 0 Ph = 7.2 . There was no reason this should have happened. This happened to our friend once before...and it turned out to be an air leak in the pressure line...and the pump sends so many micro bubbles into the tank it oversaturates the water...and kills the fish. I'm just confused as to why the Pacu died and not the ID Sharks...he had to have been one of the hardiest fish..and lived thru many near disasters over the years.
Anyway, it's 4:11 am now...and I don't see any sleep for me in the near future...the remaining fish are settled in, and I'll be checking them every so often. The tank is so bare...and I miss the pacu already.
I feel like I've lost one of my best friends..

This was a massive, 3,240 gallon tank with obviously, some very big fish and it's very likely the cause of death was from oversaturation of oxygen.

 

[ncjharris]

Going back to the tank - I would hazard a guess that the cloudiness is a bacterial bloom, perhaps caused by the extra oxygenation of the water (i.e they are aerobic bacteria)

 

[kramers]

Well its 8:45a here and I went on and unplugged the pump about 10 mins ago and will recheck periodically. Is there anyway of testing the O2 %? Checked the water temp and its about 79 degrees average. My heater is set on 77. Should I lower it a couple of degrees to help dissipate more O2?

 

[ncjharris]

You can get o2 tests., try your LFS

 

[Trance2006]

I have a major question,

I went home yesterday afterschool only to find my water somewhat cloudy. I thought It was a bacteria bloom but the light wasn't onm. However My pump has been airning the water since Friday night. Can that cause a huge bacteria bloom? Please your response is highly urgent. My tank is a AGA 20 Gallon

Ammonia - 0
Nitrite- 0
Nitrate - 0
ph- 7.4

PLEASE!!!

 

[steelhealr]

Whoa..whoa...whoa.....let's get our facts staight here. You cannot increase the concentration of oxygen greater than atmospheric without increasing the partial pressure of oxygen. I hate to do the science thing, but, oxygen is a gas with kinetic energy. Increasing temperature increases kinetic energy and cooling decreases it.

As you heat water, you increase the kinetic energy of the water and gases and you can drive oxygen out. If you cool it, you can maximize the total oxygen dissolved. DIFFUSION keeps a level of equilibrium in the water. To 'supersaturate' oxygen in water you must increase the partial pressure of oxygen and that occurs with compression or increasing atmospheric pressure.

A glass of water in a hyperbaric chamber, compressed to 2ATA's or twice the level of atmospheric pressure will NOT become cloudy but will increase the amount of dissolved oxygen by 2X. If air is at 21%, at 2 ATA it will be 42%. SH

SH