The hardest part of the whole "bucket canister" idea would be the lid.
The hardest part in my design is getting it to purge and prime automatically after filling the canister halfway with water. My design allows for a tiny bit of bypass through 3/16" tubing which will be connect to the intake of the pump which should allow the pump, after its been primed, to siphon the air from the top of the canister to the bottom of the canister, through the pump and out into the tank. This will eliminate the need for the canister to be "shut down" now and then due to trapped gasses.
On the other hand, I could just run a tube from the top of the cover, in the center, and attach it to the output line from the pump externally from the canister. This will also allow it to purge and prime easily without any bypass at all. Problem is, if and when trapped gases get into the canister, I will have to turn the canister off. I also have to find out how to connect the tubing in a way where its resistant to leaking under pressure.
I always design canisters on paper with the a pump siphoning water out of the canister and not pumping water into the canister, lots more pressure to deal with.
If you have the pump on the top, you eliminate this bypass since you don't need a tube plumbed into the intake of the pump. Obveously air rises and will escape naturally as the canister primes.
The problem with having the pump on top, is you need to start the intake siphon some how, otherwise, your canister will never purge or prime.
This is why I had the idea of the pump on the bottom, like the Fx5, so I can fill the canister 50% with water, turn it on, and eventually should purge 100%. On paper it works, in reality is another story.
The cover is the next hurdle. Soon I will be starting a very high paying job and I should be able to start this project back up, atleast order a new cover (I melted mine, oppps, damn oven) so I can test to see how much pressure, or atleast, how much height the cover can take.
Canisters are not as EASY as everyone thinks. Once you really start to get into it deep. You start noticing things such as, allowing pressure differentials work in your favor, creating the correct flow path, make it resistant to high pressures, make it durable, allow it to be able to purge and prime easily, design the filter with large cross section surface area so clogging is reduced and flow can be increased and more..
I like it when others bring up ideas. Gets me thinking again. So if you have other ideas, let me know. I suppose we can throw comments back and forth to see what is a good design.
