Dirty Sandbed

Has anyone found a good way to clean their sand substrate? I regularly vacuum mine but it is constantly dirty. Any ideas?

Use a soft toothbrush between the glass and substrate to lift out the algae/ cyanobacteria. Then suction the surface of the sand with an airline tube.

you have blue green algae on the sand and glass.

clean conditions up, reduce dry food, make sure the lights have a 6500K rating, increase aeration/ surface turbulence and oxygen levels.

I glued an old credit card on a stick and push it down between the glass and the sand....but otherwise I leave the sand to the Malaysian Trumpet Snails.
(I have 3-4" of pool filter sand in my 60g and believe that the best bio-filtration is with undisturbed sand.)