3/4" plus 3/4" PVC question

[JMorris271]

With 2 - 3/4 inch pipe drains,will their sum produce the same volume passing into my sump as a single 1.5" pipe. Does anyone know of a chart that I can go to and figure that answer?

Thank you for your help.

[phillrodrigo]

I would use atleast 1inch. After doing research I found out drains in 3/4 sshouldn't be used unless your gonna have very little turn over. Mine was for a 20 so I wasn't to worried but would have went 1inch if I found it out first

[JMorris271]

I would use atleast 1inch. After doing research I found out drains in 3/4 sshouldn't be used unless your gonna have very little turn over. Mine was for a 20 so I wasn't to worried but would have went 1inch if I found it out first

That is why Im combining the 2 drains.I am stuc with 2 3/4 "s holes.
and asked the question that way.

[formsix]

Not the same -- the 1.5" pumps significantly more. Think about it this way. If you calculate the area of a circle with a 3/4" diameter you get *way* less than half of the area of a circle with a 1.5" diameter.

That said, if you have two 3/4" pipes to work with, that's certainly better than one!! It's not ideal, but I think it's workable. However, I'm a big fan of the herbie system, and in that you leave one of the drainpipes completely open as the emergency drain. I'm not sure if it would be wise to go that route with your two pipes, but that might be preferable to using both to drain. Hopefully someone with more experience can chime in on that issue.

[dumbfireman]

http://www.reefcentral.com/forums/showthread.php?t=1814606

[dumbfireman]

that thread has some good info and charts.

[JMorris271]

Not the same -- the 1.5" pumps significantly more. Think about it this way. If you calculate the area of a circle with a 3/4" diameter you get *way* less than half of the area of a circle with a 1.5" diameter.

That said, if you have two 3/4" pipes to work with, that's certainly better than one!! It's not ideal, but I think it's workable. However, I'm a big fan of the herbie system, and in that you leave one of the drainpipes completely open as the emergency drain. I'm not sure if it would be wise to go that route with your two pipes, but that might be preferable to using both to drain. Hopefully someone with more experience can chime in on that issue.

I always have considered the open channel drains to function as emergency drains in an emergency situation.

[JMorris271]

http://www.reefcentral.com/forums/showthread.php?t=1814606

Thanks a lot Fireman. Just what I was looking for.:thumbsup: