One macro algae Mexican turbos may graze is Asparagopsis. Asparagopsis is the algae usually referred to as "red cotton algae". Other large grazers, at least ones I've had in my tank, tend to avoid Asparagopsis. Although I can't tell from the picture you posted, I'm not sure that you have Asparagopsis. Asparagopis is very fragile and finely filamented, and tends to have a red-pinkish color under most light. It can grow in areas of fairly low light intensity, and IME tends to grow in eddy areas where detritus can accumulates.
From appearences, it looks like your tank is doing great and you have nutrients well in check. There are algaes that can find a niche and persist in low nutrient tanks. Wire-brushing is a fairly good way to manually control algae, IME, especially if done out of the tank. It's enlightening to see how much detritus can be under an algae mat. I'd hate to see any of your colonies get damaged when doing that, though.
If its not Asparagopsis, a Diadema urchin may be an effective control. Small Diadema can grow quickly though, and will outgrow a 75G tank in a few months, IME. Diadema is a good grazer for stony coral tank as it tends to keep the rock grazed bare, preventing alga mats/turfs from getting a foothold. Diadema also seems fairly safe with stony corals, although it will tend to sample especially when it gets too big for the tank.
