professor_rob Posted January 21, 2015 Report Share Posted January 21, 2015 Hi Quick question, I am going to set up one of them DIY PVC overflows, I am having trouble finding an Airline Check Valve. Does anyone know where you can get one from? Tried Bunnings, Masters a few irrigation places...no luck. Thanks guys. Link to comment Share on other sites More sharing options...
yellows Posted January 21, 2015 Report Share Posted January 21, 2015 Is that one of the clear ones with black top Try your local pet shop or The Tech Den that's where I got mine if there the one's you need Link to comment Share on other sites More sharing options...
brodie7744 Posted January 21, 2015 Report Share Posted January 21, 2015 Your local fish store should help you out there mate Link to comment Share on other sites More sharing options...
Craigo Posted January 21, 2015 Report Share Posted January 21, 2015 Have heaps of the then, drop round and grab some Link to comment Share on other sites More sharing options...
aquaholic99 Posted January 21, 2015 Report Share Posted January 21, 2015 I wouldn't use a check valve on an overflow. Just slide some airline up and siphon all the air out. The check valve could fail, as could the seal where it joins. (I used to have over 100 PVC overflows mostly 40 mm and untold numbers of water bridges). Link to comment Share on other sites More sharing options...
professor_rob Posted January 21, 2015 Author Report Share Posted January 21, 2015 I wouldn't use a check valve on an overflow. Just slide some airline up and siphon all the air out. The check valve could fail, as could the seal where it joins. (I used to have over 100 PVC overflows mostly 40 mm and untold numbers of water bridges). Thats is a good idea, but I have no luck trying to get the airline down the pipe and then up the other pipe...just gets stuck at the bottom double bend Link to comment Share on other sites More sharing options...
crusty76 Posted January 21, 2015 Report Share Posted January 21, 2015 Thats is a good idea, but I have no luck trying to get the airline down the pipe and then up the other pipe...just gets stuck at the bottom double bend Try a sinker on a piece of line put that through ur pipe then tie ur airline to the line and just pull it through easy Link to comment Share on other sites More sharing options...
dids4bubs Posted January 21, 2015 Report Share Posted January 21, 2015 check valves do fail on them it sucks its happend to me just about burnt the pump out on my sump lucky its a out side tank water everywhere. Link to comment Share on other sites More sharing options...
professor_rob Posted January 21, 2015 Author Report Share Posted January 21, 2015 Try a sinker on a piece of line put that through ur pipe then tie ur airline to the line and just pull it through easy Hi, the PVC pipe is installed now, would be hard to remove it...hence i cannot get the airpipe to go back up the other pipe... will have to try a check valve... can you plug them up after to avoid failure Link to comment Share on other sites More sharing options...
Sacrilicious Posted January 21, 2015 Report Share Posted January 21, 2015 You know whats better than a check valve? 2 or 3 check valves in the line. If one fails... the others might hold Link to comment Share on other sites More sharing options...
Heintz.G Posted January 21, 2015 Report Share Posted January 21, 2015 If all fails get one of these tie the airline to one end, I use it for cleaning filter hoses and they are very flexible 1 55M Pipe Tube Cleaner Tool Double Head Brush FOR Aquarium Filter Pumpe Pipe | eBay Link to comment Share on other sites More sharing options...
Grubs Posted January 22, 2015 Report Share Posted January 22, 2015 (edited) I would install a small nipple, and put 10cm of 4mm plasticised irrigation drip line (thick wall, wont collapse under vacuum, and fits the CO2 checkvalves) with a CO2 check valve on the end of the hose. Suck the air out as required, and then place a hose clamp on the hose to hold the vacuum (so you are not relying solely on the checkvalve). If the checkvalve fails over time - easier to replace on the end of the hose. For the checkvalve I'd try a CO2 checkvalve that is spring loaded. eg: Ista Spring Stop Check Valve FOR Aquarium CO2 Diffuser Bubble Counter AIR Pump | eBay The 4mm irrigation line is softer than CO2 line and will be easier to clamp shut. The CO2 line is a bit rigid and I dont know that you could clamp it without splitting it, but does has the advantage you can get it transparent so you can see what is going on. I use the 4mm poly irrigation nipples that are barbed one end and threaded the other. Drill a tight hole, use a toothpick to smear the inside of the hole with a small amount of PVC glue. Wait a bit for the PVC to soften - then screw in the threaded irrigation barb. They can get brittle after a few years and too much side pressure can snap them.... but soft plastic is very easy to drill out and replace. ... or for maximum reliability - cut your DIY overflow open or rebuilt it with the line in place snaking around the bends. Again I'd recommend the thicker wall 4mm irrigation line as it wont kink going around the bends - esp when you try to suck on it. Edited January 22, 2015 by Grubs Link to comment Share on other sites More sharing options...
aquaholic99 Posted January 22, 2015 Report Share Posted January 22, 2015 Thats is a good idea, but I have no luck trying to get the airline down the pipe and then up the other pipe...just gets stuck at the bottom double bend You shouldn't have a double end at both ends...? If you do, I would use a thin copper wire (spiralled around the airline) so you can push it through any bends. Here is a poor photo of one of mine. Confusingly, it's in 2 pieces though. There is another PVC overflow running on the filled tank in background. Link to comment Share on other sites More sharing options...
professor_rob Posted January 22, 2015 Author Report Share Posted January 22, 2015 Thanks for all the help guys, think i finally got it sorted. Another issue I had was trying to set it up so that it wont suck up my RCS... when i put mesh over the overflow pipe it creates air pockets and stops it running. Finally got it all sorted now. Link to comment Share on other sites More sharing options...