The search for solutions to getting enough light in the tank continues. The light panel fitted last year does not seem able to meet the needs of many of the plants typical of a south coast shallow rock pool. Whilst red algaes, particularly fine ones, seem to thrive, macro green algaes simply do not.
Crusting pink coralline algaes do well, but branching ones are stunted.
Green hair algaes are a nuisance unless heavily grazed by snails.
Recently I trialled a 50W LED floodlight, supposedly equivalent to a 500W halogen lamp. It falls far short of expectations! I built a new hood to allow the installation of 8 of these if the 1st seemed adequate for purpose - but at £65 each will probably not buy more.
A few days ago I also tried 6 no. cool white 10W LED downlights. These too disappointed.
Images were taken with a Canon 5D Mark 2 using a 50mm f1.4 lens at f2.2, 1/60th second at ISO 400
That, for anyone who isnt into photography, indicates that light levels are really low.