Do you mind giving the genus names for your fish? When I type in "p ngaeus", my computer keeps asking if I mean pangassius...
Sorry about the algae eater deal. From what I know, most of the fish that we get, come from rivers and streams that are incredibly dark due to tannins and tree shade. Chiloglanis fish from the Congo river look like Plecos, but I think they're mostly wood eaters.
If your tank is short enough, you could try to make a stand of Dracaena sanderiana. Do not put the leaves underwater, use the woody "bamboo" looking parts underwater, and keep the leaves above water at all times. It's often sold as "lucky bamboo", and used in feng shui.
So many fish to keep, not enough aquaria.