While your tank is cycling it will develop algae at differnt times most will go away with time it can take up to a year or so for a tank to stabilize in the mean time just keep good maintanance, Mexican turbos I don't think do sand I know mine don't maybe you need some more flow in areas where algae is building. Give your tank time and don't pick at it to mch let it stabilize on it's own in itsown time
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