yauger November 14, 2012 Share November 14, 2012 To prevent a back siphon on the stirer I'm using a one way air valve. However it seems I need to replace them once every couple of months. Is therw a better way of preventing a back siphoning into my water top off tank? Link to comment Share on other sites More sharing options...
Origami November 14, 2012 Share November 14, 2012 Did you see this post, Josh? http://www.wamas.org/forums/topic/53358-check-valves/page__view__findpost__p__448106 Link to comment Share on other sites More sharing options...
ctenophore November 14, 2012 Share November 14, 2012 Yes, exactly. That's what we recommend in the manual as well. Works very well. I'm surprised about the comments re: peristaltic pump backsiphoning. Link to comment Share on other sites More sharing options...
STEVE November 14, 2012 Share November 14, 2012 The Avast WILL back siphon...Changing that check valve is part of that deal! I just took off the long clear tube on mine, that brings the water in (below the water lever), still keeps my ph up from 7.9 to 8.15. Just got so tired of changing that valve. Link to comment Share on other sites More sharing options...
yauger November 14, 2012 Author Share November 14, 2012 Yeah that will not work. I have a tunze top off and that pump will push the water to the top of that T. Is a cruddy little check valve the only solution? Link to comment Share on other sites More sharing options...
ctenophore November 14, 2012 Share November 14, 2012 Try a valve directly after the tunze pump output to slow it down. Not really a good idea to have kalk going into your system that fast anyway. The tunze pumps I've used in the past pushed a pretty fast stream of water, probably 5-10 gph. With kalk you want to aim for about 1 gph. That flow rate should prevent water from going all the way up the anti-siphon branch of the tee. Link to comment Share on other sites More sharing options...
matt November 14, 2012 Share November 14, 2012 yeah, use a gate valve with a splitter like you were slowing a sump return pump going to your display (routing extra back into sump/reservoir)...then use Doug's T diagram on the line with the reduced/gated flow. or, buy lower-head-rated top-off pump Link to comment Share on other sites More sharing options...
Integral9 November 14, 2012 Share November 14, 2012 You could put a check valve on the top of the line to stop the outflow over the top. The valve would then open to break the siphon. Kind of putting it in reverse, so to speak. Link to comment Share on other sites More sharing options...
yauger November 14, 2012 Author Share November 14, 2012 You could put a check valve on the top of the line to stop the outflow over the top. The valve would then open to break the siphon. Kind of putting it in reverse, so to speak. can you break this down for me? I can't visualize what you're writing. thanks! and for the other suggestions of reducing the flow from my pump is a bad idea for my setup. My pump is located a good distance from my stirer and reducing the flow rate would make things difficult for me. on a side note do you have a replacement union fitting without a hose barb fitting on it? I really would like to get rid of the tube going to my sump and change it with PVC. any help? Link to comment Share on other sites More sharing options...
ctenophore November 15, 2012 Share November 15, 2012 You could put a check valve on the top of the line to stop the outflow over the top. The valve would then open to break the siphon. Kind of putting it in reverse, so to speak. I like this idea in theory but I suspect the crack pressure of the valve is higher than the negative pressure produced by the falling water. Worth a try though, and I would be curious to know if it works. Yauger, what he means is to install the check valve at the end of the open (siphon break) leg of the tee, so it's pointing down towards the tee. Water can't be pushed out by the pump, but air could be drawn in to break the siphon when the pump shuts off. I'm not sure what the distance of the tubing run has to do with the need for a higher flow rate in your case. The pump will still produce essentially the same head pressure to overcome any upward tubing runs, just the flow rate will be reduced. I think the valve on the output will work well if you give it a try. Pushing water through the stirrer as fast as a wide-open bilge pump produces may cause significant pH swings; have you not noticed that? Link to comment Share on other sites More sharing options...
Integral9 November 15, 2012 Share November 15, 2012 Cten. has it right. You'd put the check valve at the top of the line. But orient it so that it would stop the flow of water up, and open to allow air to fill the tube when the pump shuts off. So the flow arrow on the valve would be pointing down the tube. I think with a non-spring check valve, the cracking pressure (which I am taking to mean the pressure needed to open the valve) is essentially zero as the only thing holding the valve closed is the reverse flow of the water. Once that is gone, the valve would fall into the open position via gravity or if oriented sideways, a slight pressure differential would be all that's required to overcome the friction to open the valve. Link to comment Share on other sites More sharing options...
STEVE November 15, 2012 Share November 15, 2012 As I mentioned before, I took the long clear tube off (feed tube from fresh water) of my Avast stirrer and now the water level is below the fitting (air gap) so there is no possibility that it can backflow. I thought this was an easy fix. Like I said, I use the Tunze ATO (as does Josh) and the pressure alone will stir the kalk. I dont think this would be great for a parastolic pump because the lack of pressure. I have not plugged in my Avast in 2 montsh.I will show you on mine Josh. My ph stays between 7.98 and 8.20, I could raise it just by adding more kalk, currently only using 1/2 cup. Link to comment Share on other sites More sharing options...
dandy7200 November 15, 2012 Share November 15, 2012 Guys, the tee method will work, it does not matter what pump you use. If it is a high pressure pump just put the end of the tee higher. You can also put a tee INSIDE your RODI top off bucket and put a small john guest ball valve on it, simply close the valve enough that only a little bit of water comes out of it when the pump is on and the rest goes to the stirrer. When the pump turns off the siphon will break. Link to comment Share on other sites More sharing options...
dandy7200 November 15, 2012 Share November 15, 2012 Pro rendering here.... If you do it like this just be sure to secure the tee to the bucket so it can't fall below the water line. Untitled by firefliesdelray, on Flickr Link to comment Share on other sites More sharing options...
yauger November 16, 2012 Author Share November 16, 2012 Dan!! Long time sir... thanks for the tip. I will give it a go, hope it works. Link to comment Share on other sites More sharing options...
dandy7200 November 17, 2012 Share November 17, 2012 Dan!! Long time sir... thanks for the tip. I will give it a go, hope it works. Howdy Josh. Yeah, been a crazy past 2 years but I am finally setting up my tank again so I plan to be around these parts a little more often Link to comment Share on other sites More sharing options...
.jpg.7bfaca13382600fc0d1da29d2e298192.jpg)
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now