Hi,

I made my water change last week on my 20 gallon tank with 15 watt light.
The tank is now cloudy with brown algae on the walls. I went to aquarium
shop and he said that i may have distroyed a lot of bacteria in my last
water change. He suggested that i buy CYCLE. But since the PH of my tank is
not changing (PH 6.5) I think the cloudy water is due to algae spores???

My tank has about 2 large java ferns, 1 amazon sword that is not doing well
and is slowly dying, java moss
and 2 other stem plants. I have a DIY CO2 and light my tank 10-12 hours a
day.

Can brown algae boom cause cloudy water, should i remove the DIY CO2.