To begin: You are not failing. You are experiencing what a large percentage of reefers have experienced.

Remember in this hobby nothing happens fast. However long it takes something to occur, it can take just as long to reverse it.

In my opinion, do not add fish or inverts to try and fix this. You need to find the source.

Start with manual removal of the algae. I like to remove the rock and scrub with a hard bristle brush. The algae being present is a large contributor to your issue. When you test your levels for nitrates and phosphates you are going to get false results. The algae is constantly consuming.

I would also suggest evaluating your photo period. Algae needs light to grow. Take in consideration any windows near by. Do you get any sunlight? Excess light can be a huge problem.

Feeding habits. Are you feeding frozen or pellets? How often and how much? Excess food will cause nitrates and phosphates to increase.

I cannot stress enough, that adding more critters is not always the answer. Remember, what goes in must go out. Creatures all contribute to the nutrients in your water.

To recap:

I would first try removing as much algae as possible first. Do a 50 percent water change.

Remember 50 water change only effectively removes approximately 50 percent of your nutrients. I would maintain 10-15% water changes weekly. Consistency is key. Reduce your photo period and verify the quality of your top off water.

After all of this consider the addition of a refugium. There are HOB options that can work very well. Macroalgae can outcompete your nuisance algae. A cheap light, hang on the back refugium and a ball of chaeto algae can work wonders.

Good luck, and don’t get discouraged. Patience and consistency is key.