cistern overflow

[merebank]

can i fit a syphon to my cistern that does not require an overflow

[plumbbob]

Yes, provided the syphon is the correct height to ensure if the cistern were to overfill, the water will flow down the syphon before it reaches the top of the cistern.

Measure the internal height of cistern and the depth of the normal water, then choose a syphon with a height between the two.