I always have algae growing on my coco or rockwool and it’s never been a problem for me. Never seen anybody put straw on exposed roots when running ebb&flow (flood&drain) but it might be possible.
Here is a little crop I just finished a couple months ago in a 2x2’ tent. The 6 plants were growing in stacked 4x4” and 3x4” Grodan cubes simulating a solo cup grow. All 6 plants produced about 3 ounces each and had absolutely no issues with the algae. I’m also positive the roots wouldn’t have grown so well and most likely would have died off at the edge of the cube if it wasn’t for the natural sunblock protecting them from the light.
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