Oxygen and fish growth...it's true!

  • We are currently upgrading MFK. thanks! -neo
esoxlucius said:
It's way more complicated than just oxygen levels. Tank size, feeding regime, quality of food, stocking levels, compatibility of said stock and each hobbyists individual nitrate tolerances all play a part.

Your oxygen levels might be perfect but your fish could still become stunted if all the others issues are neglected.
Click to expand...
I totally agree with this and find when whatever the result, combinations of environmental factor are often at play.
In the study below, it shows how elevated nitrate effects a fishes ability o process DO.
Exposure to Nitrate Increases Susceptibility to Hypoxia in ...The University of Chicago Press: Journalshttps://www.journals.uchicago.edu › doi
or below where falling pH in combination with high nitrate works as a deleterious combination
Simultaneous exposure to nitrate and low pH reduces the ...National Institutes of Health (.gov)https://www.ncbi.nlm.nih.gov › articles › PMC6977012
 
  • Like
Reactions: SilverArowanaBoi
As neutrino neutrino said too much of a good thing isn't good...a controlled growth test of similar fish with high oxygenation would be interesting. To my uneducated eye it especially seems to influence the growth of fry. I also have wondered exactly why higher temps suppress oxygen. Molecular activity at heat temps? Competition with other gases in water? Or is oxygen chemically transient in water columns?

I remember once being told about the importance of surface area for tanks which is why some configurations aren't as good for oxygen transfer.
 
  • Like
Reactions: SilverArowanaBoi
The molecules move slower in colder water so retain more DO.
As water warms, molecules move faster allowing oxygen molecules to be driven off.
The only time I've ever had trouble with too much O2, is in winter when water in distribution pipes gets super saturated under pressure.
This can cause gas bubble embolism if fish.
So in winter when I would do water changes, in Milwaukee and the tap water water 39'F and super saturated, I always sent water to my sumps 1st, as opposed to the main tank.
In that way, it would mix, and by the time the new water passed thru the pump, excess super saturated DO was driven off.

You can tell if cold water is super saturated straight from the tap, if you draw a glass, and it clears from the bottom up.
 
  • Like
Reactions: FINWIN, neutrino and SilverArowanaBoi
This reminds me of a cool Canadian educational cartoon called EUREKA! It would come on locally in DC on WETA-26. One chapter deals with heat/cold transfer and molecular speed. Its on Youtube, you have to search by each chapter listed in Wiki.

Unit 1: Force and Energy[edit]
  1. "Inertia"
  2. "Mass"
  3. "Speed"
  4. "Acceleration I"
  5. "Acceleration II"
  6. "Gravity"
  7. "Weight vs Mass"
  8. "Work"
  9. "Kinetic Energy"
  10. "Potential Energy and Speed"
Unit 2: Simple Machines[edit]
  1. "The Inclined Plane"
  2. "The Lever"
  3. "Mechanical Advantage and Friction"
  4. "The Screw and the Wheel"
  5. "The Pulley"
Unit 3: Heat and Temperature[edit]
  1. "Molecules in Solids"
  2. "Molecules in Liquids"
  3. "Evaporation and Condensation"
  4. "Expansion and Contraction"
  5. "Measuring Temperature"
  6. "Temperature vs Heat"
Unit 4: The Conduction of Heat[edit]
  1. "Atoms"
  2. "Electrons"
  3. "Conduction"
Unit 5: The Convection of Heat[edit]
  1. "Volume and Density"
  2. "Buoyancy"
  3. "Convection"
Unit 6: The Radiation of Heat[edit]
  1. "Heat as Energy"
  2. "Radiation Waves"
  3. "The Radiation Spectrum"

Eureka! (Canadian TV series) - Wikipedia
 
Without specialized equipment you can't. I've never worried to much about it. Good surface agitation is all you really need. I like to add additional airstones as it has increased fry grow out for me.
 
Caperguy99 said:
How do you ensure appropriate oxygen levels? Just wave makers and bubblers? How can you confirm how much saturation you’re getting?
Click to expand...

I don't have a specific method other than multidirectional water movement. Multiple airstones situated below hob overflow and then the powerheads hitting that motion from different angles. The fish seem to love it and it doesn't blow the fry around at all. The 125 and 225 have 2 and 4 inch air stones. The substrate stays clean of most debris.
 
You must log in or register to reply here.
MonsterFishKeepers.com
Top Bottom