Lately, some of my corals started to bleach and dont look so good wile in the same time some of my other sps corals are getting back there coolers ....strange
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Plus I have an outbreak of red green cyano bakteria that covering my rooks and killing some of my zoa garden
I dont know exactly what is the causes
I checked the netrat phosphate and all values are not detectable
i decided to do a 10 precent water change sooner that i had to
and change the osmosis membranes after 2 years that i did not change them it seems
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and clean my send that i cleand 3 months ago
and i was amazed to see how much dirt gets out of this sand every time i clean it ,and i have to say i got no idea how the hack it gets there
i dont understand how reefers keep dsb in there tanks
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i just keep 1 cm of sand in my tank and i keep it just where you can see it and not all around the tank (in the front mostly )
here are some pics
replacing the membranes
the new membranes ....looking good (Although the TDS with the old membranes was also 0 TDS )
filling the water after the water change
the clean sand back in the tank