Hi guys... need some helpful input. I've been wanting to install backgrounds into some of my cages. For the tropical and semi tropical I have been using the GS and coco bedding method (w/ wood and plants inserted appropriately) but no water feature. Now it seems I'm going to need a water feature (the front 2/3's of the tank 10's and 15 Hi's mostly). Got 2 new baby Oscars and there HUNTING all the other fish in the tank so everybody's gonna get put into separate water feature in other tanks. My questions are these... I've seen others use GS to create water features... does it hold up to constant wetness and still RETAIN the water? Yes yes I know the GS is covered by silicon just have to ask. The other question, I also like the faux rock backgrounds(adhesive tile grout and acrylic cement fortifier) I've seen here and wonder if those materials can be used in an aquatic or semi-aquatic environment. I've only seen them used in arid settings. I mean will any harmful chemicals leach out with constant exposure to humidity/dampness and water?
Also, I'm planning on having several of these tanks so I figured it would make sense to use a centralized filtration source (i.e. a sump). The tanks will all have a false bottom so there will be internal filtration with the plant roots and biological filtration w/ the gravel and LECA. Any idea or opinions on how to set up the plumbing for this? How do I maintain constant and appropriate water levels in each enclosure? Is it just a matter of regulating the intake out take flow? HELP!!

