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the best way to lower salinity is to utilize PWC
only. Since there is no livestock in the tank you do not have to be as careful as it there was. Take out about three gal
. of Sw
and replace it with FW
. If you are using a "swing arm" SG
meter, just know that they are not very accurate. Get another one and compare the two.
on a side note...if this is a new tank and you have no livestock in it, I would consider ditching the UGF
. It is a bit out-dated and there are much better forms of biological filtration available.