There is no doubt in my mind you know what you are doing in regards to semi hydroponics.
I was only trying to note to Roy and others who are trying to use an all perlite mix, that an all perlite mix would work better in a semi hydroponic system as you describe on your website, then in the way that they were using it. I gather they were using an all small perlite mix and pouring water from the top flooding the mix until it drained out of the bottom of the pot. The particle properties of small perlite causes to much water to be held by the mix, and decrease air space. While I didn't say this initially, I suspect that pouring water from the top also breaks down the perlite quicker. Perlite is brittle. The jostling that perlite goes through from top watering would cause perlite to breakdown into smaller particles.
The sentence I noted from your website talking about medium in a semi hydroponic system: “The medium is another key component of the culture technique; it must be inert so it won't decompose, fairly uniform in particle size so it provides lots of free air space, and must provide good capillary (wicking) action to keep it uniformly moist. “ doesn't work for an all small perlite mix or small particle mix, but does work for the larger one-half-inch diameter PrimeAgraTM spherical ceramic medium that you use.
The reason spherical ceramic medium you use provides lots of free air space is because of the large size of the particle in relationship to the fill size of the pot, and because of the uniform shape (spherical). A small perlite mix provides small air space between particles and even less as the irregular shapes settle. This is all in relationship to fill size, in this case the pot.
For Roy and other others using a mix of all one type of medium of the same shape and "size": It is good to sift your medium to make sure you are getting a uniform size. As Ray pointed out in his post, smaller particles to the particle size wanted will fill in any free space.
Now to fit in more with the forum: #!!!*!# darn #/#?weasel#*!!^$!#*..?#4 you [EMAIL PROTECTED] ;-) Boy that was good for me. Was it good for you?
Mark Sullivan
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