Backyard Aquaponics
A place to discuss aquaponics

Hi,
Why do we need a siphon in Aquaponics? I have setup a grow bed that overflows into the fish tank when filled up. WIll that not work ? Plants are growing well.

Would like to hear your comments



Thanks

The reason syphons or timed F&D is used in a GB is to exchange the GB water volume so it doesn't become anaerobic and also introduces oxygen for the plants and bacteria. More recently its found that constantly flooded GB's work well, BUT, a CF bed still utilises a standpipe and media guard where water is drawn through the bed and out.

In your design, it may work for a while but will eventually become anaerobic and stagnant. Plants will struggle and possibly crash your system.

+1 on Charlie.

Plus you want to lower the water level to 5cm below the media. You'll have a host of problems if it's too high.

agree with previous posts, particularly CBB about the water level and media.

if you were required to stay with a design like this some improvement would be gained by extending the tube to the bottom of the container and protecting it by putting inside a container with holes (to reduce blockage risk).
This would help to ensure that the 'old water' is taken out as new water is added from the top thus providing some level of circulation. In a system like this it is still a good idea to have a tap to drain it completely every once in a while.

personally I would have a larger diameter pipe, as the one shown would block easily.

p.s. what is the second tube for that enters the box midway ?

Thanks for the above helpful answers . The second tube is just the oxygen tube to the pump , and does not enter the GB.
The inlet tube goes to the back of the GB... deep down. The overflow is at the top at front. . Hence the old water is pushed first from the bottom and then drained through the top.

However as Charlie had pointed out , I have noted a green layer formation ( algae growth) in my Stone gravel, hence it could be an issue later for plant growth.

Just a beginner here, and miles to go....

most likely because your water level is at surface. If your water level is too high you will get algae regardless of the system style you adopt. Even with a good system you still get a little bit of algae at the discharge and similarly a little bit in the fish tank along with the 'good' green slime. All OK in moderation.

you will end up with root rot (stem rot) if you dont lower the water level.