Is there anywhere that sells an adjustable weir for an Aquatop Recife Eco 24g? I saw one in a thread and would love to know where to pick one up as the built in weir doesn't skim the surface no matter the water level. I attached the picture I found showing the weir in someone elses build from a really old thread. Any other alternatives to that could work to keep the surface from developing an oil film would be great as well.