hi bro, very nice tank again.
thanks for answering my qtns and hope i can give my 2cents here in return.
for the dust, i think tht would be sand and detritus. since u are on bb, how bout pointing the wavemaker downwards so tht the sand/detritus will be in suspension to be removed by your filter wool in the sump?
with regards to the temp, although 31+ is a little on the high side, hw about just monitoring ur fishes since ur not keeping any inverts? if not, chiller would really help. no space also, if u really want, for sure have space one haha much like stocking up on fishes.
nxt alternative is fan, but higher evaporation rate like u mentioned. dont knw if its gona help, but once u knw hw much ur tank is evaporating water per day, maybe can freeze the same amt of distilled water and drop in the sump evry mornin b4 u go to work/sch. but quite a hassle though.
gd luck and happy reefing, more updates and pics of ur fishes would be co
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