By providing a method of making LED's with appropriate weight ie looking at the buoyancy factor make such LED which could float underneath water at a certain depth.

Tendris, BioSoil and Solarix in a joint initiative, have made a breakthrough in growing algae with the application of underwater LED.
This, they have done with nutrient rich waste water from anaerobic digesters in an open pond cultivation.
So this under water LED might be a viable solution to the problem of providing uniform light intensity

At Microsharp we are currently negotiating a project to develop a low cost illumination solution for use in open pond which aims to move sunlight and illuminate the bulk of a medium more uniformly. The optics have to be very low cost and survive weathering and biofoiling but the approach should work. Light is collected using thin film optics and moved to an emission surface below. We are also looking at hybrid open/closed ponds. Everything has to do with producing a solution which is very low cost.

A company by name Bionavitas, Inc., has developed a technology called “Light Immersion Technology which the company believes is a breakthrough that can dramatically increase algae yields in a cost-efficient and scalable model. The innovative approach, involves bringing light to the algae culture in both open ponds and closed bioreactors through a system of light rods which extend deep into the algae culture. By distributing light below the surface layer and releasing the light in controlled locations, algae cultures can grow denser. These rods distribute light from the sun into the culture

Skip the open ponds, to much contamination and not enough control over growing environment , a closed pbr is better.

add a hollow small diameter transparent tube inside the pond.

Another way is to stir by bubbles just as in aquarium. It will improve CO2 level and rotation will bring bottom algae to come to top and vice versa

Another method is mixed approach of the two above methods

Although my comments are not completely on topic, I would appreciate a response. Please follow my logic. In order to be involved in this business, one must be competitive, especially against the well financed firms that have employed the university laboratories. They all are using genetically modified organisms which demonstrate significantly greater efficiencies in the production of organic compounds. We must also use similar organism to compete. If this is the case, open pond would not maintain the integrity of the strain being used. The system would be infected immediately. Consequently why is an open pond being considered?
Will any of the laboratories license these productive strains? Or, will each operation have to genetically modify the organism themselves? I am new to this subject and realize that I may be missing an important and pertinent point…….

?Use of baffles in the raceway pond may provide uniform light to the bottom algal culture by Sukla - 3 minutes ago

Think about what water wieghs per gallon or liter, etc. How much energy must be spent to continue to bring the deep water to the surface all around the raceway. Are you sure you can produce this much energy to keep the stirring/circulating mechanism operating and still have enough energy and other products to sell at a profit?

Jet pumps, to move the water or simulated wave action. Technology exists, is easy to use and maintain/service. They also can be adjusted for flow or action and can be solar powered.

firstly algae can grown heterotrophic so when light intensity decrease not inhibit the growth secondly in my opinion to solve the proplem of light intensity a glass light columns put in ponds in different areas

The simplest and economicaly viable solution that i could think of is biomass stirring, which would help to expose algal cells in bottom of the pond to sunlight. The beneficial effects of stirring are without question, but one must take care to minimize hydrodynamic/ shear stress on the microalgae, which can significantly decrease productivity. Circulate the algae around the ponds using paddle wheels would be the ideal strategy that i could suggest