[trogg]

Hi. I’m designing 3 different types of self watering systems for my tomatoes, cucumbers and  peppers. Two of the systems will need topping up every month or so, so I can add the correct feed to the water supply at the same time, however the third system will use rain water which means the feed will get diluted.
what I am trying to find out is can the feed/water solution be tested for strength ? So I can top up accordingly .

ta

 
 

[Trillium]

You know we'll need pix of the units  as well as end results. We're a nosy lot.

[mumofstig]

Hopefully it is a feed that colours the water,  you could see if it's been diluted too much.
Sorry I'm not aware of a way to test it

[BostonInbred]

I cant think any accurate way of determining the dilution except by lab test, on a continuous flow system.

The only other way i can think is to have an intermediate resevoir like  a pair of butts, where you fill one, put in a measured amount of feed, and feed the plants with that whilist the rainwater fills the other one up, and  as you drain the first one out, you then dose the second one and switch over

[Yabba]

Have a read of the alternative "herb" sites, they know all about stuff like that

Based on some posts on a chilli site you'll want a ph/ec meter to tell the nutrient level in your solution.

¥

[JayG]

All I can think of is a hydrometer (as used for measuring the specific gravity of fermenting liquids) but don't know whether the variations in SG you will need to measure will be enough for this kind of instrument to work.

[trogg]

Thanks for your replies, 
I’m going to have a play with the 4 idea’s put forward  and I will take pictures and let you know how I get on.
To be honest my idea is just a mash of what other people have done, and all use ‘capillary’ as a water/feed intake.