1. Is it easier for a pump to push or pull water?
Depends where the pump is located, most pumps are designed to push water against gravity.
2. Larger diameter to reduce resistance.
Increasing the diameter may be beneficial on the intake if its flowing with gravity but has the opposite affect on the output if the output is going against gravity. You need to calculate for the extra weight/volume of more water that the pump has to push against height is a big factor here also. A pump can only push as much water through the pipe as there is room. Smaller creates the same problem of head pressure on the pump, you need to find that sweet spot. I'm sure there are calculators out there for this.
3. Circular flow
Only my opinion here but flow is flow and as long as its not creating dead spots your good. lots of factors involved like scape design, rocks and ornaments etc. all of which have the potential to create dead spots.
4. multiple pumps to 1 pipe.
Depends on pumps, head pressure, piping size etc. But what you stated makes sense to me.
To much math for me.
Dan
Depends where the pump is located, most pumps are designed to push water against gravity.
2. Larger diameter to reduce resistance.
Increasing the diameter may be beneficial on the intake if its flowing with gravity but has the opposite affect on the output if the output is going against gravity. You need to calculate for the extra weight/volume of more water that the pump has to push against height is a big factor here also. A pump can only push as much water through the pipe as there is room. Smaller creates the same problem of head pressure on the pump, you need to find that sweet spot. I'm sure there are calculators out there for this.
3. Circular flow
Only my opinion here but flow is flow and as long as its not creating dead spots your good. lots of factors involved like scape design, rocks and ornaments etc. all of which have the potential to create dead spots.
4. multiple pumps to 1 pipe.
Depends on pumps, head pressure, piping size etc. But what you stated makes sense to me.
To much math for me.
Dan