Does anyone know the amount of GPH lost per 90 degree elbow in a 1'' Sch. 40 PVC line? Also, is it worth the risk to install Sch. 200 PVC as opposed to sch. 40? If you don't know, the 200 pvc can carry more water b/c of its thinner walls, but, it will wear a hole quicker than the 40 b/c the water movement actually creates friction in the pipes and over time, will "burn" or rub a hole in the PVC--which means the 200 would get a hole much quicker. Anyways, any input would be appreciated.
Drain loss
- Thread starter ericmcj31
- Start date
Man, you must be moving some serious water to worry about wearing down your PVC pipes from the inside out... 
I don't have my book handy, but the Reef Aquarium, Vol 3 has a breakdown of pipe sizes and head loss for different fittings. You should be able to google and find it.
Either way, it's almost definitely not worth going with anything but Sch 40 PVC- the loss will be negligible...
I don't have my book handy, but the Reef Aquarium, Vol 3 has a breakdown of pipe sizes and head loss for different fittings. You should be able to google and find it.
Either way, it's almost definitely not worth going with anything but Sch 40 PVC- the loss will be negligible...
the reason I ask--is I have my tank drilled with 2-1'' holes (for the drain), and 2- 3/4'' holes (return). I have a Mag 12 pump--the pump is really overpumping the water being drained. I have a valve on after the pump, but it is nearly 1/2 shut off. I figured that over time this isn't good for the pump to be that much shut off. From what we figured, a 1'' line can drain about 600 gph, and the mag 12 should pump around 1000-1100 gph with 3-4 feet of head. Again, any input would be appreciated.
Cutting back a mag (or most pumps) doesn't hurt them, as long as they're cut back on the output side - the impeller just spins. In fact, they typically only use the power needed because of the linear resistance (1/2 flow == 1/2 power used).
A 1" drain can hold more than 600gph, can't it? (I can't remember- it's been a while since I've used pipe that small). Another thing you can do to increase drainage capacity is using a slightly larger drain pipe- such as a 1.25 or 1.5" pipe, then a reducer to 1" - I have no idea why that works, but it does...
The other thing to factor is that a 1" drain capacity and 1" drain with a hose attached (such as a drain line back to the sump) is different. You might want to just test your Mag 12 on one 1" drain and see what happens- if it's enough, use it for primary, and use the second for your emergency overflow...
A 1" drain can hold more than 600gph, can't it? (I can't remember- it's been a while since I've used pipe that small). Another thing you can do to increase drainage capacity is using a slightly larger drain pipe- such as a 1.25 or 1.5" pipe, then a reducer to 1" - I have no idea why that works, but it does...
The other thing to factor is that a 1" drain capacity and 1" drain with a hose attached (such as a drain line back to the sump) is different. You might want to just test your Mag 12 on one 1" drain and see what happens- if it's enough, use it for primary, and use the second for your emergency overflow...
