My friend gave away live Rock and I started a new tank about 50 pounds.. Tanks been up few mons.. The live rocks around 4 years old...my new tank is 35 gallons no sand. And just hang on filter and it never clears.. The rock looks good.. I don't know why this never clears not sure how to fix this.. Is not having sand bad? Since I don't have much for a filter other then a hang out filter? I'm thinking not enough biodiversity ? Thanks for tips.. Salt 0.25 cal 420..dkh 8.0 nightrates are low 0.2 and phosphate I don't check however I use only ro water feed super light and only have two clowns in tank