Tank looks great now (though I do miss the sand). Good riddance algae. Thanks for sharing updated pics and letting us know how you did it (I'd still say the high TDS RO water and probably overfeeding were what were causing it?).
There shouldn't be silicates leaching in any significant quantity from aragonite sand. Now if you used playground sand which is silicate, then maybe, but that sand looks like aragonite to me? (did it fizz/dissolve in vinegar?).
tank looks great, im surprised the tang police havnt blown you up though...
I really like the look of the aquascape.
Could the resin rocks be leaching phosphate and fueling the algae?
I love the minimalist aquascaping in your tank. It really emphasizes the corals.
Is the algae issue something you have been dealing with all along, or is this a new problem?
I sold the tang away:fun2: . Even at 1.5inch, the poop is flying all over my tank and creating a mess. Yup, so i am cleared. Not guilty. :bounce3: