So you may know by now that I'm a university student. This necessarily means that I have no money of my own. This is the list copied from djkaty's thread, from which i have removed the things that one probably could not make themselves, and I want to know how much of it I can piece together myself for cheaper than it can be bought: - Aquarium - at least 190 liters (50 gallons) - not copper-based treatment as this will kill the octopus - Mechanical filters, need to remove ammonia, nitrate and nitrate, chemical filter will kill octopus - Hydrometer (swing arm) to test salinity - Protein skimmer - must be rated for 3 times the size of the tank - Carbon - TWP / RO/DI filter - Air pump with wooden diffusers to agitate surface layer of water I've looked at the DIY section on ozreef.org and apparently you can put together a tank, a sump, and a skimmer. (Preferably acrylic, as I don't like breakable things.) How cheap can I get on these?