Use of Lasers in Controlling Pest Algae and Corals

[CalmSeasQuest]

I've been doing some research on the use of Laser light in eradicating and/or controlling certain pests frequent in marine aquaria. These include,

• Aiptasia / Mojano
• Blue/Green Algae including Valonia and Bryopsis
• Xenia
• GSP
• Virtually any other unwanted pests such as vermetid snails, predatory crabs...

In theory, it should be a simply process to eliminate any unwanted life from an aquarium, and easily prune others (think of it as a lawn edger for an area of Xenia or GSP.) I'm also curious about the possibility of using Laser to "cauterize" part of a coral subject to RTN. It might also work well for laser-fragging soft corals such as Z&Ps as it could be done while the coral was still in the water.

The most common laser pointers (< 5mW) do not generate anywhere near enough energy to be effective. Higher power lasers are now available that can emit enough energy to instantly "boil" the targeted pest, while avoiding damage to adjecent corals. The primary challenges with this approach,

• Cost - Higher power lasers are expensive.
• Safety - Eye protection is an absolute nesessity as intant blindness is possible should the beam (or potentially a reflection) strike your eye.
• Legality - There are FDA imposed restrictions on the sale of Class IV lasers (<50mW) that make them difficult (read expensive) to acquire.
• Risk to livestock - Caution will have to be mainted to prevent fish from being struck by the laser. At very high power settings, even viewing the point being lased "might" result in damage to their eyesight (still investigating this concern.)

I've ordered the components to build a 1800mW / 445nm laser to test the above theories and develop effective practices. More to follow...

ps. Sorry for including this in the LED section - It required a sub-prefix and no others seemed appropriate. The light source in a laser is a light emitting diode