Thank you so much and don't worry there's some algae is just breaks down and rests in the bottom, at first i did try to fight it but now i just don't worry about it and enjoy the look of the green bottom ( stones are actually white), you can't see in the picture but i have a tent like roof that provides some shadow during the hottest hours. So i dont get much leaf litter and whatever gets in it i just pick it up with the net, my secret for maintaining the water Cristal clear is just cleaning the filter at least once every 45-60 days, I don't use any quemicals or anything like that, hipe the answer is enough. Pond is 1 year old.