What do i look for in a pH meter?

I’ve found this on a dutch ebay-like site

http://link.marktplaats.nl/508174677

It doesn’t list a brand, and i bet it’s a cheap piece of junk (can’t expect much for 18,50 Euro =^ $ 24, can i?), but my gut says it’s still a lot better than those pieces of paper. Anyone?

Hi there,

I was drawn here by the TED talk, and had a look around. I have a few comments and some questions.

I think the format of the website (blog + comments) is confusing and not the best environment for a collaborative effort.
Changes to the instructions and the official documentation cannot be added freely by the community, like they would be in a wiki, but they are cherry-picked by the “Core Team”, who has privileged write-access to the source.
This is not bad per se. Many big open source projects have a selected team of committers, and new members must prove their worth with valid contributions before being granted write access.
However, open source projects also have a clear procedure that contributors can follow in order to “patch” trunk – or in fact, any branch. According to the Open Source Initiative, if such a mechanism is not in place, then it’s arguably not an Open Source project.
Also, Windowfarms is not a code project, it’s a hardware/design/documentation project. Therefore, there is no risk of breaking the build (because there is no build), and Wikipedia shows us that there is a lot to be gained, at the very least in terms of polish and formatting, if write-access is granted to a wider user base.
I think allowing any registered user to edit the documents, plus having a selected group of super-users with special entitlements in order to manage high-traffic, prominent pages, would be a good balance.
Similar suggestions towards a more open, transparent and functional means of documentation and discussion have been repeatedly proposed in some comments of this website, but I have not seen a response from the “Core Team”.
Are there any plans to improve the situation?

I also notice that users are supposed to register in order to read the allegedly open source documentation. This made no sense to me, so I had a look at the small print, where it says “We require that you agree in order to view the free instructions on how to build windowfarms. This is for legal reasons that would endanger the community if we did not require registration and acknowledgement.” Quite how the community would be “endangered” is not explained, but there are two links, one to a fairly big website (http://www.openhardwaresummit.org) and one to Windowfarms’ Terms of Service.
In the main page of the Open Source HardWare website (which is interestingly a wiki), there is a section spelling out the OSHW Statement of Principles. It reads, “Open source hardware is hardware whose design is made publicly available so that anyone can study, modify, distribute, make, and sell the design or hardware based on that design.”
Yet, in Windowfarm’s Terms of Service, we learn that Windowfarm’s instructions are available under (an old version of) the Creative Commons Attribution+Noncommercial+ShareAlike license.
I believe that the Noncommercial module is unnecessary. In fact, some would argue that adopting a permissive license can benefit a project’s popularity and adoption, which is apparently the overall goal here. Linux is a notable example of how this can happen.
Furthermore, the Noncommercial module seems at odds with the above-mentioned ability to “sell the design or hardware based on that design”, mandated by the OSHW, as well as the Free Redistribution clause of the Open Source Definition by the OSI.

Noncommercial module notwithstanding, however, it still makes no sense to me that users are asked to register in order to just read the instructions. How is that a legal necessity? Aren’t Windowfarms instructions already protected by the license and copyright statements, much like e.g. every Wikipedia article is?
In fact, can’t anyone, well within the rights granted by the current license, freely divulge those instructions (under the same license) on a mirror website to anyone on the Internet, without requiring any registration whatsoever?

Finally, given the use of the noncommercial module, I take it that only non-profit organisations can sell hardware based on Windowfarms’ designs. Does that mean that Windowfarms itself, which does sell the hardware, is a registered non-profit organisation? Apologies if I missed the details, but they do not seem to be widely publicized.

Thank you for any insights.

I am in Shanghai and having a difficult time sourcing the materials needed.

If I have a text file I can attempt to use http://www.nciku.com/ or google translate to get the list in Chinese and look for places.

Please let me know.

I think this project is fantastic, although I’m finding the site a little difficult to navigate (that could be due to the spammers trying to sell me coats and headphones though )

Has anybody given any though to the potential contamination from the plastic bottles (BPA, PET etc)?  The water bottles (in the UK) say that they shouldn’t be refilled, this isn’t just a cunning ploy by the water companies to sell more product, it’s also because the chemicals from the plastic leech into the water.  I ‘imagine’ that will the plastic bottles sitting in direct sunlight, some of those chemicals would also leech into the plants.

This is my only concern with this otherwise impressive system.

Is anybody using any alternatives to plastic bottles?

It turned out to be a lot less work than expected and building was fun.

Currently I’m trying to grow some strawberries. I have no idea a what interval (or perhaps continuously) the pump should be turned on and I’m experimenten with nutrients. Who knows, it might just work…

It’s still leaking a bit.

I’ve had some problems figuring out how to get the airlift to work efficiently. In my case pointing one needle up and one needle down seems to work.

During the “experimental phase” I discovered that my design wasn’t yet cat-proof.

I’m thinking about doing the vertical window garden, as I already have a large floor window garden.  Can anyone say if they have to rotate their bottles to help keep the plants growing straight?

I rotate my floor pots or else they all start leaning  towards the window and it also seems like I get a better plant when I do this.

Plants below are all window grown dirt-based.  Thai basil, Italian basil, queen basil, and the bottom pic is of a pineapple i’m growing indoors. ( never thought I could do this)

Did anybody try using .5L bottles instead of the 1.5L Bottles? From what i’ve read, i would expect that space is an issue for only some plants.

If the vertical space is the first problem, i could cut off the top of the bottle and space them further appart, put the plant higher in the bottle, so their effective root space is just as big as in the 1.5L bottle.

The advantages would be space, taking less sight in the window, and less weight.

The disadvantages, i don’t really know, there could be many, but i would assume they’re all space-related.

I’d like to think this would make a kick-ass mini-window-farm for maxing out cress and other really tiny plants.

I’m about to build my first WF. While I generally love the idea of growing food at home, the free design of WF 3.0 is a bit of an eyesore as such. I wanted to come up with something that’ll still be a full grown window farm, but is still approved by the wife.

Update: Second Draft

Thanks for the input everyone. I came up with a simpler less work intensive solution: flower pots. I went to a hardware store to look at PVC pipes, and stumbled upon some plastic orchid flower pots. They seemed right size and only cost 1,99 a piece, so I got two for testing. The pots have a dent in the bottom, kinda like wine bottles. See the drawing. This type of construction prevents the container from draining out completely. Not sure if this is a good thing or a bad thing.

I also decided to try string instead of metal wire, since I couldn’t find proper parts for attaching the wire to the pots. Here’s a picture with initial string based suspension:

Drawing:

First Draft

Here’s my first draft on an improved design. I didn’t bother drawing the irrigation system in detail since it’s not really important in this context. The main idea is that we’ll encase the water bottle, suspension system and the irrigation system in painted PVC pipe. Any other pipe should do as well. My first draft doesn’t depict how exactly the pipe and bottle are attached to the suspension system. I haven’t really made up my mind on how I should implement it. Anyway, the PVC pipe should be sort of fixed into the suspension wire system, while the bottle and the plant are easy to remove. It’s not really feasible to remove the pipe, since the wires and the irrigation hose run through the pipe.

Comments and improvement ideas welcome

See the next post for construction details and pics.

How on earth do you get the inflation needle to stay onto the check valve!?

I have average petco check valves (the ones recommended in the online WF set up) and basketball inflation needles. The two will not stay together and after an hour of functioning they come apart. It’s so sad and such a tease, adivce would be greatly greatly appreaciated!

Ciao ciao

Hi all

So, I’m new here, but highly experienced in hydroponics generally. Here are a few very basic improvements/suggestions to the WF system that I would consider beneficial. forgive my waffling in advance as this is all top of my head (but useful never-the-less)

1. use BLACK SPRAY PAINT, not white. here’s why;

a) black paint will definately prevent ANY light getting to the root zone, as compared to white which, as I have found in my own DIY systems, is less efficient at this (algae formation as visual evidence)

b) root zone temp. As a basic principle, the warmer the root zone the faster the root growth and so, plant growth (up to an optimum temperature, above which becomes detrimental). So, black paint in sunlight has better heat absorption properties than the reflective white paint. In theory, black paint would assist the root growth more than white by keeping a warmer root zone.

2. a possible UPGRADE?

adding a water heater to the reservoir (set at 18-20 celcius) would also promote root growth for WF in the colder windows of winter in which the water temp may drop to a point of plant growth inhibition.

3. increase the RESERVOIR SIZE.

a)The smaller the reservoir, the quicker the P.H can shift. a very important aspect of hydro growing, if this shifts too much (and it will if not checked) the PH will go beyond the zone of nutrient absorption and lock-out nutrients to the plants… which stresses and ultimately reduces efficiency of the plant. increasing the reservoir will add an extra buffer zone for human error (forgetting to check p.h) and makes the hydro system a little more forgiving. for example. in a DIY dripper system I constructed, the 4L reservoir (feeding 4 plants) went beyond the p.h absorption parameters within 24 hours, due to the plants using far more Nitrogen than other nutrients in the solution. Upon upgrading to a 10l reservoir the plants now maintain a stady p.h for a number of days.

b) the smaller the reservoir, the quicker the E.C (or T.D.S [total dissolved solids]) will increase. Plants use far more water than nutrient so in a small reservoir in which far more water is being used than nutrient, after a period of even a few hours (if the WF is full of plants) the water could have dramatically reduced whilst nutrient has only minimally reduced. So, the relative concentration of nutrient (E.C) has increased. This is not good for control.

4. buy an E.C meter. NOT ESSENTIAL BUT RECOMMENDED FOR OPTIMUM CONTROL AND GROWTH

Now, I will state that I do not know to which degree readers of this post will be acquainted with E.C etc so I will quickly, and rather superficially, explain it in basic terms.

E.C (electro-conductivity)  is the concentrations of ions or nutrient in a solution (dissolved nutrient strength). As a basic rule, the higher the E.C the stronger the nutrient concentration, the benefit of an E.C meter is that it gives you control over the feed strength BEYOND knowing what you put in at first. So, if say, you carefully measure 10ml of nutrient feed into 10L of pure water, and the E.C meter (digital reading) reads an E.C of say 1.0 as a rough example(note this is purely for exemplary purposes), which is fine for your plants age and stage etc. you add this to your reservoir and begin the feed regime. After a  few days, the plants may have used 2l of water, yet only 0.5ml of nutrient along with it, so now, your carefully calculated nutrient strength is out the window because you now have 8l of water with 9.5ml of feed…

so; from 10l-10ml= 1ml/l (a balanced strength)

to 8l-9.5ml = 1.18ml/l (now stronger)…

So, now you know, to bring equilibrium back to the nutrient strength, you must add water until the E.C drops to 1 again. without this meter, it is very difficult to know how much of what has been used by the plant.

so,  just a few basic ideas, this is my first contribution (actually currently procrastinating from studying for an exam)and I hope to add more in depth ideas and suggestions when I have the time to write them up after my exam period next week.

any questions or whatever really, please don’t hesitate… I love talking hydro!