The store I work for has four main systems. One for freshwater cold, freshwater tropical, marine fish only, and an invert system. Each tank has a drain screen and are those part of the same system are attached together through pvc
piping. The piping is done in a way so that gravity carries the water from the tanks to the sumps in the back. Each sump is fitted with a large powerful pump the return water. The water is first filtered through a micron bag and there are all sorts of other equipment attached to the marine systems.
Each sump, except the invert system sump are equipped with two 6 to 7 foot high towers about 3 feet in diameter filled with bio balls. We use live rock right in the sump for the invert system. The marine systems have chillers, protein skimmers, UV
sterilizers, and ozonizers. The freshwater cold system also has a chiller. We might hook a UV
sterilizer to it too. Carp type fish can carry a lot of pests. I was lucky enough to find a source of locally bred fantail goldfish. Ones shipped from places like Singapore and Hong Kong seem to be having a more than usual problem with parasites for the past year.
With how our systems are set up, gravel vaccing can be made very simple. We use a long garden hose that can reach all the tanks and drains into a pit where the sumps are at in the back. The sumps are in the ground. A large pit was made (tiled) to put the sumps in and has a few water drains to the city pipes. The garden hose is fitted with a vaccuum cylinder with a valve to control the flow of water. The tanks fill up by themselves. Just need to keep an eye on the sump levels and if they get too low, we just stop vaccuuming and replace the water through the sump. If the water level of the sumps get too low, the pumps run dry and burn out. What a pain in the *** that is...lol.
Another thing that was set up nicely are the air valves for added aeration. We use thin piping behind the tanks and there's a valve every so many inches to match up with a tank. The air pumps are located in the back with the rest of the equipment and heaters for each system are located in the sumps.
What ever you do...do not use undergravel filtering for anything.
A vitality in a LFS
are hospital and quarantine tanks to keep the main systems from very upsetting outbreaks of disease. These tanks should only be fitted with heaters, sponge filters and something for the fish to hide in. Stand up systems or 'wall units' would need to be fitted with much bigger bio filtering but the bare tank concept remains the same. The only exceptions are for animals that have to have sand to keep them happy like jaw fish and small wrasses, loaches and eels for example...and always provide non porous objects for hiding. If an animal cannot hide, it will stress...especially if it is weak and/or sick. Non porous objects are less likely to harbor harmful bacteria and parasites as well as easy to clean.
There's so much more to running a LFS
. It is very expensive, so be prepared. Do not skimp on equipment to try and save a few bucks. In the end it'll only end up costing you more. Start off with top of the line equipment and do a lot of researching. There's a major difference between the upkeep of a private tank and the upkeep of a public retail outfit.
Good luck and feel free to ask any questions.