hi i have got a 130L fish tank with a long power head filter that i keeped discus in after 5 weeks or so the water started to go green so i give the tank lots of water changes the water was still green so i moved the discus to a littler tanks and they are now ok with my 130l i took all the green water out and started again with rocks and plants. now after a week it has started to go green and there is no fish in it at all just the filter that i hadnt clean from the discus. why is the water green and there is no fish in it just plants and rocks?
what can i do?
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what can i do?
) 
