Backyard Aquaponics
A place to discuss aquaponics

Thanks TCLynx for the info on no holes overflows.Has been a great info input for my next auto siphon for the growbeds.

Current system uses flow from timer set pump cycling water to GB.
Next plan is to expand existing setup to include a big aquaponics system that is housed in a greenhouse/hot house.Any info about the plastics used to cover the green house/hothouse.

http://www.svensson.com.au/pages/greenhouse_products/greenhouse_cover/ls_solar_ultra_-_outside_screen.html

Google of "greenhouse plastic" brings up 29 trillion million results

TC, thanks for the pics of the check valve in place. We still need to add that and your discussion and subsequent pics were perfect.

Going back a bit, have you built a no holes overflow water bridge with auto siphon such as you show in the one diagram?

Credit where credit is due. From the May no-holes-overflow thread:


(viewtopic.php?f=1&t=3392)

Using the checkvalve is great, though. I had one on mine and was still putting the end of the sucktube under water. D'oh!

I've been using silicone to seal my sucktube. It does have to be replaced every once in a while, but is a bit more flexible than PVC glue.

I hate to sound like a goofus but I finally understand what TC was doing here thanks to the illustrations. I don't know how I missed this thread. Thanks TC.

Good tip. I had been wondering how to use an overflow tube to get as close to bottom as possible. I'm thinking I'll drill a 1/4 inch hole at the top and stick in 1/4 inch tubing. I've found that to be fairly air tight for the pressures ap uses. And if it happens to not work, I'll silicone around it. Sticking the other end into the tank is a good idea too, easily accessible when needed and already attached. Plus, if the overflow is working and no water is coming out of the air tube, you know you have air that needs to come out.

I have had failures of the check valves on occasion so always make sure that you have a second overflow in place if using no holes overflows!!!

ken oath.

I have through mere reality come into contact with the restraints of all "over the side" overflows:
when it freezes, they are the first to clog
and when it thaws, they are the last to thaw

for me no more "over the side" overflows

frank

I guess how much redundency depends on how much you have at stake. Extra drains, spare pumps and powersupplies, even alarms, levels, temps, flows, 02 are good insurance. These look great for indoor glass aquariums.

You could stick in the smallest water heater you could find into the overflow pipes.

Or as very short section of heat tape, would probably be too long by a lot though.

I had never heard of heat tape. Looked it up and now I have, thanks. Do you think sticking an aquarium water heater as close to one of the overflow ends or into one of the ends would be enough to keep the whole thing from freezing? That would be easier to accomplish and maintain.

I would set it up with a heater inside the intake, sized to allow plenty of flow around heater. Important factors might be
>aquarium heaters generally don't allow settings near freezing: how to turn on at low temperatures?*
>these heaters are made for aquaria, while heat tape is not, so less concern re leaching

On the other hand, around here winter temperatures generally do not cause plumbing damage, so a lots is exposed, but it sometimes freezes, so is insulated with rags or special foam insulation. That might be a far simpler method: simply protect the vulnerable exposed tubing. Our local hardware store sells the stuff for pipe up to about 40mm/1.5". The foam is about 10mm thick.

I've given them a good go and I think that I'll convert to holes overflows. I've found them to be more expensive and a big maintenance issue. Now that I know more about how siphons work I'd go for an auto siphon every time now.

My origanal attraction to no-holes overflows was so that I wouldn't have to hole my liners or tanks and risk a leak. Now I think that the operational risk if a no-holes overflow were to fail completely out ways the risk or even the expense of small leaks.