So for those of you who have seen my mini hydroponics herb garden (https://www.instructables.com/id/Mini-Hydroponics-Herb-Garden/), here are some modifications that I have recently made.
There were some problems with that surfaced after a couple of weeks with the first design. I'll go through this in detail and the steps I took to fix them.
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Step 1: Problem 1: the Bell Siphon
So if you read my first instructable, you would realise that the most finnicky part of the build was getting the Bell Siphon to work as I wanted it to and that took me ages to fine tune. I was finally happy with the way it was filling an draining.
Then 2 weeks in, for some reason, it decided to stop working consistently. I had changed nothing.
So... I gave up on it. Instead, my ebb-and-flow system now relies on a simple siphon using the pump and a timer switch you can get from Bunnings. Pump switches on for 10 minutes 4 times a day, fills the grow bed, overflows into the reservoir. Pump switches off, pipe functions as a siphon, and grow bed is drained.
Simple, elegant, hassle free. Works like a charm.
Step 2: Problem 2: Gravel Guard
The next problem was a little unexpected. So what I suspect is that because the plastic that I used for my gravel guard was too thin and light, it was gradually getting pushed upwards by the expanded clay pellets and eventually there was a lot of expanded clay getting into my Bell siphon. This may have been why the bell siphon stopped functioning optimally. I would have had to pick out the expanded clay pellets every few days.
What I did to solve this problem was pretty simple. I got the plastic pots I bought the herbs in, placed the clay pellets in there, and then planted the herbs. That way, all the clay pellets are kept out of the way of the now overflow pipe.
Step 3: Other Problems
And that was basically it.
So far, I've harvested the mint and basil a couple of times, and they are growing absolutely fantastically. I am very happy with them.
The only problem lies in the rosemary. I think they are being over-watered and are starting to form black tips on their leaves. I've cut down the pump to switching on twice a day so I will have to see how well this works out. Till then, good luck with everything! =)