Can you help me figure out how to promote the most oxygen with my water fall:


Is more oxygen formed when (1) water trickles down a lot of rocks with only a little hight fall depth between the rocks

or (2) flows without splashing, but for longer distances over the surfaces of evenmore rocks in a steeper but wider waterfall going through crevises

or is the best solution to have (3) the water fall nearly 10" from a rock ledge directly into a pool of water which will make a lot of bubles upon contact, instead of having the water trickle down a steep wall of rocks, loosing momentum.

That's not really an easy question. It is water movement that allows gas exchange. Generally, the more splashing, the more water movement but if the choice is between just a single splashy falls and a longer stream with water rippling, the long route would probably generate more oxygen. My suggestion is to use a combination of the things you mentioned using stream and waterfall sections.

25c worth - Definitely good question. Since air bubblers are used in aquariums and ponds, and sprayers in hatchery lakes to oxygenate the water, my guess would be that more bubbles and splashing exposes more water to the air interface and would therefore be better oxygenator.

I experimeted with waterfall heights and found that a minimum 6" freefall drop created good turbulence (bubbles and sound effects) in collecting basin below falls; and subqeuently designed 2 @ 6" drops and short stream rather one 12" drop and longer stream.