I have a question that I can’t find an answer too. I decided that you guys would be the best source for information.
This question is more academic in nature and maybe some of the science behind my thought process is flawed.

I am asking about marginal trout water, lakes and ponds, that have adequate depth to provide cold climate but become devoid of oxygen at that depth during summer. If you were to aerate the water with a diffuser or bubbler you disrupt the thermocline and bring warm water down to the depths and defeat the purpose of creating good trout habitat. I know you can elevate the diffusers to try and leave some undisturbed cold water or only run them at night to minimize thermal problems. I understand that these oxygen devoid zone are occurring because light is not reaching to these depths and photosynthesis is not able to occur, and that bacteria are respiring using up any oxygen that was there.
What would happen if you created a bunch of grow lamps in a water proof glass casing, and they were vacuum insulated to minimize heat transfer, and submerged them to the bottom of your marginal lake and had them running off of solar power 24/7 during the summer? Would these lights be able to support enough plant life or phytoplankton at depth to oxygenate enough water to provide safe summer refuge for holdover trout? What they give off too much heat to be useful?
Thanks for any and all responses. I think that this could work and I think it would be a reasonable solution to low oxygen at depth.
Thanks again,
Oliver

I love your thinking out of the box! I'll have to think about this one for a while.

Bill Cody is our resident phytoplankton expert among other things so I'd value his input.

Bill?

I have been pondering this on my own for quite a while and I can't find any "good" answers. With new lighting tech and solar tech an idea like this might work and be affordable. Ten years ago it would have been way to expensive.

And keep in mind it takes someone to think out of the box to come up with something like this so it's no surprise you aren't getting any answers. Most people including some scientists don't go out of their comfort range when it comes to ideas.

One negative I see is how far will the light will carry in the water and how many lights you would need to to make difference? It's also possible you could get phytoplankton going well in a small area but would be overwhelmed by anoxic water that comes in via natural infiltration. Another negative would be how long the lights stay clean enough to diffuser optimum amounts of light. Films on objects develop quickly in the water. Just a few thoughts of course and by no means meant to deride your idea.

It's probably something that has to be done to determine it's feasibility and effectiveness. At first in a small pond and with frequent data from an oxygen meter. Probably off a pier or with remote sensors.

I have seen these in homes. They work well. In a pond tho? Same priciple might work?

http://www.lowes.com/pd_580501-58-TGF+01...amp;CAGPSPN=pla

Well you could just get high gage fiberoptic cable and run it to the depth. Not sure if it would be enough light

This would be a problem. However if most lake only have 4-6 weeks of trouble time July to late August. Cleaning them a few times might not be such a huge deal.

Make a home made one of these

http://www.agoberlin.de/hydroair/gew_restaur/ago_gwr002_e.html

Wow. That is amazing thanks

If you have ever seen the inside of an algae culture incubator, you will realize you probably cannot create enough light and bright enough to grow algae in the hypolimnion. Even nature (sun) does not have enough or create enough light intensity on a cloudy day to keep phytoplankton growing adequately to produce a surplus of DO. Fish kills can happen due to lack of DO after several cloudy day periods. Research the light intensity needed for growing algae cultures. Now extrapolate that to the volume or area of your hypolimnion.

Thanks Bill!!!