I have never heard of anyone using algaecide on a marine tank. Do you mean NoPox? And simultaneously double-dosing a bacteria culture. Please let us know how this works out. I don't say it absolutely won't work, but if regular algaecide, it's not by-the-book, as t' were. You might be safer to rein in the magic-bottle solutions and go slow from here on. You may have a successful cycle, but ask around about a product. We've tried most of them.
As for your cloudiness, gravel dust very frequently makes cloudy water and won't settle and clear until individual dust grains have coated with enough bacteria to make them sticky and sink.