In my experience, most screens do come off. The faucets had to be assembled and you should be able to disassemble most if not all of them. It just may require a little ingenuity. If you absolutely can not get the screen out, you should be able to at least remove the business end of the faucet and backflush and/or soak the screen that way. Many manufacturers have lifetime warranties on their products and I would not be reluctant to seek a replacement if I had a malfunctioning faucet that could not be dissassembled to clean off a screen.

I am happy to report Blanco stood behind its promise and made very good on a nearly expired 5-year warranty. We did not get covered for high plumbing costs, but Blanco sent us a check for about $130 MORE than we paid for the product. (Priceless good will, in my opinion.) That nearly covered cost of Whiterhaus' Vintage III replacement from on-line seller. The Whitehaus product, one of few traditional models made in Antique Copper w/ real brass, seems well made, and the quality of all parts, except PLASTIC spray push handle, compares to Blanco's when we purchased in 2006. The design of Whitehaus is similar but not as attractive as Blanco's; it's as though the faucet handles and spigot pigged out on Kiblasa. OTOH, maybe a thicker design will avoid trouble the sleaker Blanco had with corrosion clogging faucet and decreasing flow. I would not buy anything ID'd as "metal" (the sprays of many brands) or made in China, e.g., Danze, a line I understand is affiliated with American Standard of Delta. I wish American makers had offered the color, style, and quality we needed.

If you were planning to mix 100L batches of nutrient you could opt for one litre of micro stock per 50 batches (5000L), basically 20ml of micro stock per 100L of solution. You would gear the concentration to match the complete formulation so, for example 20ml/100L with 1L of calcium stock and 1L of macro stock for 100L of working solution. That way if you want to increase or decrease the strength it makes things much easier. 30ml of micro with 1.5L calcium and 1.5L macro for 100L equals a 50% increase. I would keep the iron (Fe) seperate and make up the stock so 1ml per litre provides 1ppm of Fe. Using 100ml of stock for 100L gives you 1ppm of Fe, if you need 1.2 use 120ml per 100L etc. 1L of stock would provide 1ppm in 1000L, 2ppm in 500L etc If you put the iron in the micro stock you`ll lose the option of adjusting it independantly which can be useful.. The calcium nitrate will need to be kept seperate, although it is compatible with potassium nitrate and magnesium nitrate, useful if you need to reduce the chemical weight in a macro stock to improve solubility. You can only get so much chemical to dissolve in a given amount of water at a certain temperature and each chemical solubility is different. Finding the individual chemicals at a good price will be the biggest hurdle, i came across this site (melbourne based) but the prices are pretty steep compared to here. They carry a 2 part called Hysol Twin Tomato but dont provide any analysis, it might be worth a look, they might be able to source a bag of kristalon if your lucky ;) http://www.duralite.com.au/hobby-growers/ I`m in blighty, currently minus 6C with 4" of snow on the ground, so not great considering its technically spring.

Thanks kudzu. Maybe I need to try to get to a showroom that has one where I can unscrew it and see how accessible the inner parts are for cleaning. My concern is more so what happens if there is debris down in the head - so not where it connects to the line, but inside the head. Sounds like you've found a way to scoop stuff out of the aerator yes? Delta did say that the only option for cleaning is the clean the hose or soak the head in vinegar and if there are actual particles in there I would need a replacement head. Which of course would be ridiculous as it sounds like I will need to clean it out multiple times a year. Do you live in relatively new construction or have an older home where the pipes need regular maintenance? I think that is a big part of what is at issue here. When the pipes are turned back on the air pressure really shoots a ton of crap into the heads. It has been useful to watch the super take apart a head, remove the aerators, and get crap out of them.