Tell me what you think: AqAdvisor - Intelligent Freshwater Tropical Fish Aquarium Stocking Calculator and Aquarium Tank/Filter Advisor This is from me combining two of my tanks to save on some space. If it doesn't work out I'll just keep the two tanks separate. If it does work out, could I add a couple guppies in it? I know they produce a lot of waste, but I'll be doing 75-50% water changes weekly (more so because it seems hard to change any less, and it hasn't stressed out any of my other animals too much). Also, I have a different filter, but I forget that type. If filtration is a concern I'll upgrade. I'll also be adding some shrimp and a few snails (say three mystery snails), but I assume that their bioload will be negligible.