Hey guys, I've got this funky algae in my 125 gallon tank. Below is a picture:

Notice the slight algae hair that's visible at the edges of the leaf. The white granules is just sand that settled on the leaf.
It used to be growing on my driftwood, glass, and plants. So, I got a bristlenose pleco and a bulldog pleco and they cleaned it all off the wood and glass, but they won't touch the stuff growing on the plants. I also tried some cory cats, who won't touch the plants, and some oto cats, which got sucked into the fast flowing filter and died there.
I've been manually rubbing it off with my fingers when I clean the tank, but that's a losing battle. Tonight I decided to see if my mollies in my 30 gallon would eat that algae, so I removed a plant from the 125 and put it in the 30 and sure enough, the mollies are tearing into the algae.
So, I figured my 2 largest mollies would probably do fine in a tank of juvenile American cichlids and clean off my plants for me. The jack dempsey, however, is a jerk and has killed one of them and will likely kill the other if I don't remove him.
So, what else can I do? The 125 has way too many plants to put them in the 30 for cleaning and small fish get eaten in the 125(unless they're a cory or catfish, in which case they're left alone but they don't clean the plants). I'm concerned because the algae appears to be smothering and killing my leaves.
Thanks for any help.
Edit: I should also mention this tank gets cleaned every 5 to 7 days with a 50% water change and is filtered by a 30 gallon sump very similar to ones used by many fellow monster fish keepers. There is no sunlight reaching the tank at all and the lights are off 14 hours a day. Thanks.

Notice the slight algae hair that's visible at the edges of the leaf. The white granules is just sand that settled on the leaf.
It used to be growing on my driftwood, glass, and plants. So, I got a bristlenose pleco and a bulldog pleco and they cleaned it all off the wood and glass, but they won't touch the stuff growing on the plants. I also tried some cory cats, who won't touch the plants, and some oto cats, which got sucked into the fast flowing filter and died there.
I've been manually rubbing it off with my fingers when I clean the tank, but that's a losing battle. Tonight I decided to see if my mollies in my 30 gallon would eat that algae, so I removed a plant from the 125 and put it in the 30 and sure enough, the mollies are tearing into the algae.
So, I figured my 2 largest mollies would probably do fine in a tank of juvenile American cichlids and clean off my plants for me. The jack dempsey, however, is a jerk and has killed one of them and will likely kill the other if I don't remove him.
So, what else can I do? The 125 has way too many plants to put them in the 30 for cleaning and small fish get eaten in the 125(unless they're a cory or catfish, in which case they're left alone but they don't clean the plants). I'm concerned because the algae appears to be smothering and killing my leaves.
Thanks for any help.
Edit: I should also mention this tank gets cleaned every 5 to 7 days with a 50% water change and is filtered by a 30 gallon sump very similar to ones used by many fellow monster fish keepers. There is no sunlight reaching the tank at all and the lights are off 14 hours a day. Thanks.