I have a biocube I just reset up a few months ago. I have the in tank media basket I use with chemi pure and purigen with floss on the top in my second chamber. I also have in there the eshopp nano skimmer. In the first chamber I am trying out maxspect bio spheres at this time. I do have an ATO and I also have a doser for two part. My perimeters are normally stable and right were I need them with exception PH which I dont chase but I feel is low end(normally 7.8-8.0). Corals are hammers, torch, gallaxia, kenya, duncan, bird nest, shrooms, lots of zoa and poly, pipe organ, goni, and a few more. I also have a mini carpet and sebae with a pair of clowns. My debate is do I go through the work of adding something like the Eshopp Nano cube Refugium (Needs to fit in the original stand) and nano overflow. Everything I have is growing and seem happy how I have it and I have no nutrient issues or algae nuisance. But I know there are many benefits of having a sump having been in aquatics for some time now. I just am not sure something as small as the Nano cube will make that much difference to justify the time and money. Any input is welcomed.