as to water volume, well LTK is speaking like a true custom operator!!!! I have never looked a at field yet and said "****, why did I put on so much water". fungicides and dessicants need lots. I have been doing herbicides at 6 or 10 depending on product and 10-12.5 for fungicides, a bigger unit will let me get up 15, on stuff like fuzz should give that little bit extra coverage, ditto for reglone / heat.
I am amazed at people that still talk about low water volumes and glyphosate. I have seen 3 gpa work quite well but 24D and express are the only tank mix partners that will work at that low a rate. the higher glyphos rates we are now using conteract the tie up problems we used to have with the really low rates we were using 10 years ago - there are now 2-3x more chem in the water so can also have twice as much water without an issue as well. and conditioners help a lot as well.
The reason I speak like a true custom operator is because I AM a true custom operator and as such I have considerably more ACTUAL experience than the vast majority of farmers that only do their own. By "experience" I'm not talking about shear volume of acres. The number of acres one has sprayed has limited effect on actual "experience" if they have all been done the SAME way which most (not all) farmers do. They find something that is comfortable and works for them, (10 GPA for instance) and they just spray that way their entire farming career. Nothing wrong with that at all, it just limits their experience to ONLY spraying at 10GPA. As a custom operator, I spray the way the customer requests (within reason). Some insist on 2GPA some insist on 10 GPA, most are somewhere in between for most products so i get first hand experience in the effectiveness of many application variations. I have sprayed, under protest, a few times in conditions that I felt were not conducive to a favourable outcome and was proven wrong. I have also been shut down by a customer with weather concerns that I knew were unfounded but, if the customer says stop, I stop. It's his field and his money so it's ALWAYS his call. As far as water volumes goes, I could care less if a customer wants more water. Makes ZERO difference to me (although my wife prefers that i don't spray 10 GPA all day LOL). I have suggested that a customer reduce his requested water rates and I have suggested that a customer increase his requested water rates with explanation as to why I am making the suggestion but it's only a suggestion and, unless I feel that the requested rate will be detrimental to the effectiveness, I still leave it up to him. Fact is, however, that most of my customers leave things like water rates up to me because they know i will do what's in their best interest every time. Regarding tank size, it seems to me that the higher water volumes one wants to spray, the less value there is in 1200 gal over 1000 gal as it does not add up to many extra acres for all the extra weight but that also depend entirely on average field size. 1600 gal would be VERY nice and IMO, is a number that makes sense, again, if you can abide the increased compaction however, the point I was trying to make is that we may see a reduction in required water volumes in an effort to conserve water, starting in places like california for reasons I mentioned earlier. People tend to waste things when they are relatively cheap, often in the name of "being on the safe side" rather than bothering to be efficient. An example is insecticides. They are relatively cheap and some guys "throw it in" as a matter of practice to "be on the safe side" (matador in first pass canola is a prime example). Another example is seeding canola. How many people INSISTED that you had to seed canola at 6 pounds per acre back when seed was <$2lb and how many still insist on 6pounds now that it is "somewhat" more expensive?.