Refugium/sump: Syphoning Instead Of Drilling?

[norite]

Has anyone here set up a refugium or sump by using a syphon, rather than drilling their tank?

 

[xxBarneyxx]

I have and used a float valve to cut off the siphon if the pump failed. I wouldn't recommend it though and I only set it up this way because I didn't know better at the time. You would be better off using an overflow box. Much easier and no risk of flooding if the pump fails.

 

[SkiFletch]

I have and used a float valve to cut off the siphon if the pump failed. I wouldn't recommend it though and I only set it up this way because I didn't know better at the time. You would be better off using an overflow box. Much easier and no risk of flooding if the pump fails.

 

[norite]

There's no risk of flooding if the return pump fails if you do your sums right and have a big enough sump with enough space, and position the syphon close enough to the water surface so that if it should happen, the syphon will stop before a flood occurs...

 

[xxBarneyxx]

There's no risk of flooding if the return pump fails if you do your sums right and have a big enough sump with enough space, and position the syphon close enough to the water surface so that if it should happen, the syphon will stop before a flood occurs...

That is a very good point.... wish I had thought about it when I had it going, would have saved a lot of time screwing around with a crappy float valve

 

[SkiFletch]

Dont forget to consider the other mode of failure Norite... What happens if the siphon fails and the return pump drains the sump? Will there be enough room in the display tank to hold the extra volume of water that left the sump? And even then, what happens to the pump that is now running dry for who knows how long? Then you have to try and protect with unreliable float switches/valves and you're just askin for trouble

 

[norite]

Well Ski....that scenario has already happened to me...the syphon failed because a piece of nori got sucked down the syphon and blocked the stopvalve. The refugium drained but the tank did not flood - not enough water for it to do so. When I got home that evening, the cannister filter was sucking air...! It could have been like that for hours....

But I removed the blockage and got the filter running again, with no problems. Even though it ran out of water, it's running just fine. I have now also fitted a plastic mesh to stop the syphon getting blocked like that again...

 

[SkiFletch]

Well good... Just remember, while it worked the first time, our centrifugal pumps we use for filters/sumps are not designed to run dry. Doing so for extended periods of time will wear them down and shorten their life span, so be prepared for that.

 

[norite]

Yeah, I know...I thought I might have knackered the cannister filter.... I'm going to replace it further down the line with a proper water pump, e.g. a newjet...I'm also going to tweak the syphon, by fitting an overflow weir in the corner, so I can get all the surface gunk off, and feed the flow straight into my skimmer, which I'm also thinking of relocating down there...