What size pipe for my Eheim 1250?

[mnestroy]

Background Info:
I just purchased a Eheim 1250 for my 40Gal Breeder (20L Sump)...

I plan on using vinyl tubing and the Ehiem comes with a 1/2" Barbed out...

I am going to use "U- Tube with Directional Return 3/4 inch - 1in"

Question:
I haven't seen any 1/2" Barbed to 1" but I have seen .5->.75 and then .75->1 I have these 2 adapters 'rigged' up on my tank but I kinda wonder if this is the ideal situation for flow?

I have all the adapters within the first 5inches of the pump, and the rest is 1" all the way up to the U-tube.

Should I leave it how it is? is there a better way? or should I just go 1/2" the entire way (including new 1/2" u-tube)

Thanks!

 

[sjm817]

You dont need big tubing for a 1250. I would just fit over the barb whatever fits well and go with it.

 

[mnestroy]

Well, I already kinda have it rigged up... do I leave it?

Ehiem Out 1/2" -> 1/2" Vinyl -> 3/4" adapter -> 3/4" Vinyl -> 1" adapter -> 1" Vinyl all the way up to my return...

I guess my question is is this method okay? if not i'll have to purchase a new U-Tube so that a 1/2" vinyl will fit (the one I have supports 3/4" - 1")

 

[sjm817]

Leave it. Nothing wrong with that setup.

 

[mnestroy]

Okay thanks, one more question..

Below is a photo of the u tube i'm going to use.. Whats the secret to prevent a back syphon when the power is out?

I can throw a check valve in but everyone says they arent willing to gamble on a check valve... so hows it done?

 

[Conceyted]

that type of utube shuold come predrilled with a small hole by the 90 degree locline elbow. this will prevent back syphoning

 

[mnestroy]

From Marine Depot?? I tested turning off pump and a syphon was started since the tip sits a good 2" below service

So your saying mine should have a tiny hole somewhere?? Hmm

If not where do i drill one? and how big?

 

[Conceyted]

you just need a hole somewhere that is UNDER the waterline with the return running and then out of the water as the water begins to drain from the main tank into the sump. The hole does not need to be big at all. Start off with maybe 1/16" and see if that works. all you need it to do is suck in some air when it goes to create the syphon. similar to a suction cup trying to stick to a wall when theres air allowed back into the suction.... its not possible to stick it. get it?