O2 and how much do you need ?

[Hotrodmike]

I have searched the net on what O2 level are good or bad and seem to find a lot of conflicting information . Is there a good chart or something that gives the O2 levels at different temps and gives a minimum and acceptable limits for different breeds of fish ? I know O2 saturation at maximum would be ideal but in the real world what are the real numbers ?
So far this is about the closest thing I have found .
http://www.algone.com/aquarium-artic...n-the-aquarium
Any input ?
Have A Kind Day
Mike

[Murray]

You could buy a DO meter and spend a lot of time on it. In home AP systems it is a bit like shooting a rat with a cannon.
Just have plenty of water movement, have an air pump with air stones and it will be covered.
There is actually not much difference between not enough and plenty when it comes to DO in the water, so it is a good idea to be a bit excessive in making sure there is plenty of water movement and an air pump with air stones.

[Hotrodmike]

Murray
Thats why I asked the question. I have a DO meter but am having problems finding how the readings relate to the fish themselves .
Dam you are good ! Never met me and yet you know my hobbies .
Yes I shoot rats with a cannon ,,,,,,,it's all in the loads

Have A Kind Day
Mike

[weslucky]

If DO (dissolved oxygen) gets to 3 ppm or below 3 you need to worry and fix it. Between 4 and 5 and its OK, and 6 or above you are good to go.

[Hotrodmike]

Thanks .
That pretty much is the numbers I have found so far .
At this point I have no concerns as the readings are running between 7-8 . I still would like to see a more per specie listing than a generalization ,but I guess for now I will just go with those numbers .
Have A Kind Day
Mike

[weslucky]

Okay maybe this will help you out a little.

How much DO an aquatic organism needs depends upon its species, its physical state, water temperature, pollutants present, and more. Consequently, it’s impossible to accurately predict minimum DO levels for specific fish and aquatic animals. For example, at 5 oC (41 oF), trout use about 50-60 milligrams (mg) of oxygen per hour; at 25 oC (77 oF), they may need five or six times that amount. Fish are cold-blooded animals,so they use more oxygen at higher temperatures when their metabolic rate increases.
Numerous scientific studies suggest that 4-5 parts per million (ppm) of DO is the minimum amount that will support a large, diverse fish population. The DO level in good fishing waters generally averages about 9.0 parts per million (ppm).
When DO levels drop below about 3.0 parts per million, even the rough fish die. The table in this section shows some representative comparisons.
Table 4. Effect of dissolved oxygen level on fish
Fish
Species Lowest DO level at which fish survive for:
24 hours (summer) 48 hours (winter)
Northern Pike 6.0 mg/L 3.1
Black Bass 5.5 4.7
Common Sunfish 4.2 1.4
Yellow Perch 4.2 4.7
Black Bullhead 3.3 1.1

[Hotrodmike]

Great ,that's more the type of info I was looking for . I know most could care less on O2 levels till problems occur . Being in the deep south as you well know summer is a killer and every bad year we loose lots of fish in the lakes and rivers here and that's the main reason I wanted to learn more information to be somewhat ahead of the game rather than behind .
Have A Kind Day
Mike

[RupertofOZ]

Be aware Mike..... oxygen solubity is decreased significantly as temperature rises...

As posted above... this is often when fish metabolism, growth and feed rates.... require an increase in ozygen availability....

Altitude also decreases oxygen availability...

[Hotrodmike]

Yes sir John I am 100% of aware of that and with our long hot summers thats why I am trying to learn more ,not just wait till it happens . That was one of the things I liked about my DO meter is it is temperature compensating , helps not have to think so much that gives me a headache !
I have kept one option since I do understand if water gets too hot ,you can't even put enough O2 in it . I am fortunate to have a very deep bore with a constant 65f . So I figure if you can't put O2 in just bring the temp down to where you can.
Have A Kind Day
Mike
PS I was thinking of the altitude thing with all Wendy's tinkering , mine is not a issue at 960'

[RupertofOZ]

Kewl, good to see you're on top of it Mike...

It's a general point that many members, especially new mmbers... aren't necessarily aware of...