NEED HELP STAT!

Hi! to all i had an 37g reef tank (24x24x15) and a 15g with 3 chamber sump with micro algae, 1inc. sand, 1 LR and a skimmer. its been running for about 3 months and 9 days now, i have 7 zoas, 2 blasto, 1 micromussa and 1 brain coral and no fish yet. tested my parameters and all are ok but my water looks like slight milky what is the cause of this? i alredy do water change 10% last week 3x and 50% yesterday and this morning 5% still the same. this the first time ive encounter this problem.
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