Hi I'm looking at upgrading my 40ltr tank to a juwel 180 rio and was wondering what is the best filter and heater to use please. Budget I don't want to break the bank but also want it to work! It will have sand substrate and fish wise I have at the moment 6 harlequins, 6 neons and 3 plattys, 2 female 1 male, thought I had all female!! Hoping to get a few more of each of these plus some corydoras a bristle nose and maybe a couple of something else but havnt looking into what yet. Thanks in advance.