- Location
- Hicksville, NY
Maybe I'm overanalyzing this (nothing suprising if you knew me) but I've been considering increasing the size of my overflow "U tube" to maximize return rate.
Right now, I have an Eshopps PF300 that comes with (1) 1.25" OD U tube. For simplicity's sake I will assume that the ID is the same as the OD and ignore tube wall thickness. Moving ahead with that assumption, the stock tube will have a circular cross area of 1.2271 square inches.
Moving up to (2) 0.75" OD tubes seems at the outset intuitively to increase circular area, but according to calculations two of these tubes will only yield a cross section of 0.88356 square inches.
Moving up to (2) 1.0" OD tubes goes in the right direction - you will now have a total circular area of 1.57 square inches.
Using (2) 1.0" OD tubes almost seemed like a no-brainer. That is, until I realized that I would now be relying on both tubes performing flawlessly! Suppose one of these smaller tubes lost siphon, or became plugged by a snail or some other object? I'm now relying on just ONE tube doing the job of the originally supplied 1.25" tube, which makes me uneasy to say the least.
Then I thought - why not just go up to a single bigger OD tube, say, 1.5", 2" or maybe even 2.5"? Unortunately, a 1.5" OD tube (again, ignoring wall thickness for the sake of simplicity) only increases the circular area to 1.7676 square inches, but moving up to a 2" OD tube yields a cross area of 3.1416" - a huge improvement. Lastly, moving all the way up to a 2.5" tube results in a 4.90875 square inch area, which almost seems like TOO much!
Now - I know that 1.5" OD tubes are available, but where can I find a 2" OD tube?
Thanks
John
Right now, I have an Eshopps PF300 that comes with (1) 1.25" OD U tube. For simplicity's sake I will assume that the ID is the same as the OD and ignore tube wall thickness. Moving ahead with that assumption, the stock tube will have a circular cross area of 1.2271 square inches.
Moving up to (2) 0.75" OD tubes seems at the outset intuitively to increase circular area, but according to calculations two of these tubes will only yield a cross section of 0.88356 square inches.
Moving up to (2) 1.0" OD tubes goes in the right direction - you will now have a total circular area of 1.57 square inches.
Using (2) 1.0" OD tubes almost seemed like a no-brainer. That is, until I realized that I would now be relying on both tubes performing flawlessly! Suppose one of these smaller tubes lost siphon, or became plugged by a snail or some other object? I'm now relying on just ONE tube doing the job of the originally supplied 1.25" tube, which makes me uneasy to say the least.
Then I thought - why not just go up to a single bigger OD tube, say, 1.5", 2" or maybe even 2.5"? Unortunately, a 1.5" OD tube (again, ignoring wall thickness for the sake of simplicity) only increases the circular area to 1.7676 square inches, but moving up to a 2" OD tube yields a cross area of 3.1416" - a huge improvement. Lastly, moving all the way up to a 2.5" tube results in a 4.90875 square inch area, which almost seems like TOO much!
Now - I know that 1.5" OD tubes are available, but where can I find a 2" OD tube?
Thanks
John
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