[kwirky]

I tried dosing vodka and it just led to dinos and it threw everything out of whack. The bacteria consumes the nitrate in an unbalanced manner, which led to other problems.

Since you already have a fuge have you thought about bumping the lighting on it WAY up and then dosing nitrate/iron/phosphate to keep up with the macro growth? If you have high nitrates then it means your fuge is probably light and/or micro nutrient limited.

What's the light on the fuge? For a 200-ish gallon tank, if you want it to out-compete your display lights, you need lots of light over the fuge. Get yourself a 100W COB grow light ( with a cree CXB3950 3500k, used for growing/vegging the marijuanas) with a dimmer knob (important) and you should no longer be light limited. Start it at half output. You might need two of them but the nice thing is you can add another one later.

You might see more success with chaeto in the fuge. Make sure there is adequate water flow, too, in the fuge. If it's stagnant then you're not bringing nutrient rich water to the macro algae & it'll starve itself out as it's photosynthesizing. About 10cm/second of water flow through the macro algae should be adequate, with a powerhead of some sort.

Theoretically, once your light is strong enough in the fuge and if you're keeping up on iron, you'll end up nitrate limited and will need to dose it here & there to keep it above 0.0ppm.