Hi Chris - I think I understand your question? Answer will depend on A. how long the draw tube is, b. size of motor, C. how long each day it is operaterated, D. temperature of the water, and probably a few other things such as exposure of pond to wind action. If one extends the draw tube to within 2-32 ft of the pond bottom a fountain will do a better job of mixing that pond. However a bottom bubbler will do an overall better job at turning over a deep pond than a fountain ever will,not matter how long the draw tube is. However if one want pretty, splashing water, and aestetics then a fountain wins the game.

First thing to remember is a fountain lifts and throws water into the air. Water is heavy (8 lbs/gal 5 gal weighs 40 lbs) thus very expensive in electricity / energy to do this vs moving and compressing light weight air to do the work of moving the water. The higher you throw water the more it costs. I'm not a fluid dynamics expert, but I think that just pumping, moving and lifting water is not very energy efficient compared to compressing, moving air. In terms of energy efficiency of moving gallons of water per hp & killowatts bottom aeration for moving water is very cheap compared to fontains.

Here are things to read for homework on this topic:

Which Way - Fountain vs bottom
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=29965#Post29965

Fountain or Bottom
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=30521#Post30521
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=150329#Post150329

Pump types
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=30070#Post30070

http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=30075#Post30075


Confused about Aeration
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=30388#Post30388

Homemade fountain
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=30223#Post30223

Lengthy discussion from the Q&A Archives about various types or aeration andbenefits and concerns.
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=92494#Post92494


Last edited by Bill Cody; 08/21/12 03:13 PM.
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