Your water parameter's are what matter the most, aslong as all your water readings match that of the lake the algae that grows in the tank will be similar to what grows in the lake. I add lake salts to my water which add's all the right supplements for the fish, so the algae that grows is growing in the right water conditions. The mbuna in are aquariums don't need to rely on the algae as their main food source (as we are feeding them, providing the right nutrients) so, basically their just grazing on the algae to pass time as such as this is what's in their nature to do so to survive and this is how they get their food supply in the wild. Here is a pic of my recently set-up tank (fish will be added soon) all that's in this tank is the lake salts and lighting left on for a longer period of time and i now have a great amount of natural looking algae. (btw the sand isn't pink lol just looks it in the picture for some reason
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