the VanSiphon

Correct. I have to ask, is this an idea you came up with from thin air or was there some influence on the design? Either way man excellent job, Think when i get my 75 gallon running and i break my 20 down, ill give it a shot!

 

Im thinking it has to do with a vacuum created in the sealed chamber? when you suck thru the spigot is forces water over the tank and then gravity takes over from there, well that and the pump?

 

Thanks! Frustration with my W siphon and a penny-pinching dutch heritage (thus the "van", that's part of my name ). I was trying to figure out why the old siphon wasn't working so had to figure out how it worked and why, first. Did some research on existing siphons that other people have created. Using readily available cheap materials, this seemed like a good option and did essentially the same thing.

 

Tight. K+ for sure.

 

No...the dry side has to be open to the air, thus the air spigot with the tube. You want the siphon to exist between the pool of water in the bulkhead/pipe in the aquarium to the pool of water that is inside of the siphon chamber.
If a vacuum is created in a sealed chamber then you have a siphon that will go all the way to sump, and that will fail if the pump fails.

In order to start any other type of overflow/siphon that I've seen, you start the siphon by first filling the dryside chamber, and then sucking the air out of the top of tube. Then seal the airtube so air don't get sucked back in.

One of the beautiful things about the vansiphon is that in order to start the siphon you only need to shut the gate valve, suck the air out of the chamber. The water gets sucked up through from the aquarium and fills the chamber. Then its primed an you can open the gate valve. Unless you are running very low water volume, the water will flush any remaining air through.

I would like to construct one of these with clear PVC to see exactly how well it works inside, but I haven't been able to justify the price of that yet. If anybody knows where to find cheap clear PVC, let me know....everywhere I've looked is pricey.

 

You would think it would be vacuum wouldnt you? But siphons theoretically do not work off of a vacuum principle. Although they stop working at a certain height like barometers (which would make you believe that air pressure would be a factor) I believe this design works off of surface tension solely because water has to remain trapped in both sides of the "hump pipe" as I like to think of it that goes over the tank. If that makes sense.

 

I'm not sure about the surface tension part, but the "hump pipe" and the trapped water is spot on.

 

I may be wrong and most likely am. Thats just what I figure.

 

I am POSSIBLY going to be upgrading my tank in the next few days. I hope to grab one that is reef ready but if not I will be trying to use this design on it. My target tank is a 125g so I am thinking that 2 of these would be in order to give me a good turnover. Would this seem likely? I can run 750gph on my return.

 

Stercus, if I were you, I might get the fixin's for 3....I've only run it on my 30 gallon tank, and can only vouch for that which only pushes 150gph through (way under what the siphon can handle) . 2 would probably work, but it seems close enough that a third might be good insurance, especially if you are already doing the cutting and sawing.