Lance's 225 gal tank

[untamed]

Find a way to grow something else (chaeto, maybe?). In my case, that meant finding a way to install a refugium where I didn't plan one. You have to aggressively weed the HA, while allowing the chaeto to grow. Little by little, you'll switch the nutrient uptake to the refugium and away from the HA.

May also help to darken the tank for a day off and on, while you light the refugium 24/7. Your coral won't mind a day of darkness every now and again.

For weeding, I recommend a continuous siphon. You place a filter bag in your sump, then start a siphon with flex tubing that pulls water out of the tank into the sump through that filter bag (keep your return pump running). While holding the pipe in your hand weed the algae and let it get immediately sucked away into the filter bag. You can do this as long as you can stand it.