Emergency: Aquarium Rescue!
Ok here is the thing. I was afraid you would nuke the tank when you do any things to it which is exactly why I was negative on doing anything to the tank.
BUT, now it has been done and things have happened. You and him need to realize that what you have done would never harm a healthy tank. It is only harmful because the tank was in a such bad condition.
Think about it, now the worst have happened, you can actually do everything to correct this tank and things can ONLY IMPROVE from now on!! You quit now you should and would be blamed. So WRONG time to quit!!!
Now is the time to clean the sand bed, clean the rocks, test everything, recycle and restock! Before restocking, this tank needs a protein skimmer for sure and debatable on a new light depends what you want to keep. I suggest to go simple. Stock only clown fish, mushroom, Zoa, Kenya trees for volume, Xenia for volume and any easy to care corals in the future. No anemones! No fish overstocking!
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