In my experience in the discus tank, the SAE's/Foxes eventually pestered the discus slime coats. I'd see streaks of where they attached and sucked when the lights were out. So out they went. Bristlenose will not do that. Before you add more algae eaters, why not wait and see if they are really necessary? Do you have that much of an algae problem in the tank? Beautiful tank too! Or just add another bristlenose or two. Can't beat them for tank cleaners including the glass! I used to wipe my glass down with every water change prior to bristlenose. Now there's no need to.
although im still not happy with it and gonna change a few things. i dont have an algae problem now but im seeing some black beard algae on old leaves on my amazon swords. i remove the leaves asap but i know how invasive this algae gets...i have had such headaches with it in the past. i know sae's and flagfish are pretty much the only ones that eat it but i do worry about it being controlled in a tank my size. i also always loved bristelnose plecos and am curious to how many i could keep in my tank( i am hoping the will breed so even with the agression in mind). thanks