Your design will work fine. But if you are looking for feedback I would use filter socks instead of sponges for your first section. You can use finer sponges in the second section. I would also ditch the activated carbon. In a planted aquarium activated carbon is not usually a good thing. It will suck out of the water the same fertilizers we are purposely adding. If your tank is well balanced it is also questionable how much it is doing for anything else. The only time to use activated carbon is when you know there is a contaminate in your water you need to remove. So if you are painting your house or if you add meds to the water and want and then want them gone.
Edit: if the blue line is supposed to be the water line I would also consider running everything so its under the water. That will cut down on noise a lot. Leaving it above water doesn't give you any benefit.
thanks for your response.
1- the pink thing in the first stage is a filter sock 4 inch diameter (to scale). I only designated a couple sponges below because there was space.
2- thanks for letting me know about the activated carbon! what you say makes sense, however I saw one of my friend's tank that was too orange he said the tannins from driftwood is causing that color and chemical filtration would make it more clear. I really like to have moss on driftwood. I will do further research on this
3- sorry if the blue lines are confusing! it is not the water line, the water line would naturally go over everything as it fills chambers and goes over baffle. the blue lines are supposed to show a plastic mesh/grid that supports the weight of the sponge/ceramic on top and allows water to flow freely under.
Try to make everything have laminar flow and avoid crashing water, also be aware of the desired water levels in the sump so it can handle the back syphon tank water during a power outage.
yes the plan is to make the last stage of the sump large enough to easily handle back siphon from the pump outtake and all of the water that would continue to siphon from the intake.
I am looking to see if I can use a glass intake siphon for the incoming water (as opposed to gravity fed overflow). this makes the engineering aspect more challenging becuase now the rate of incoming flow is not automatically regulated by the rate of water going back into the pump.
The reason I am trying to achieve this is because I really like the clean minimalistic look of aquascapes that use the clear glass input and outtake pipes. I have mostly seen them with canister filters though. I might have to drill the aquarium and install an overflow box anyway...