good to chat with you
majdub is fool of god, as in Sufism, the Mullah Nasrudin http://en.wikibooks.org/wiki/Nasrudin#The_Burning_Hat
is a Majdub. (the link has fables, I dont recommend reading the interpretations) Majoum is cannabis edibles, which Majdubs consume to bring them closer to god.
The current Lucasized Formula with GH Flora is still 0-8-16 as you said. Other nutes, such as PBP can also be made to approximate similar NPKMg values, for example PBPBloom @ 15ml/gal plus 5ml/gal Cal Mag.., or 8ml/gal Flora Nova Bloom
Both with target TDS @.7 of about 1300ppm (use less FNB, like 6ml/gal if your TDS exceeds 1400 with 8ml)
The original reservoir strategy I learned from pH was to dump and replace as you described, once an equal volume of addback water has reached. IOW, when a 20 gallon res, got 20 gallons of top up water, the res was dumped and refilled at fresh 0-8-16. This was not with pH adjusted water, because it works best to allow the res pH to fluctuate within a range of 5.3 to 6.3
An alternate reservoir management strategy I now prefer, is to add nutes to the reservoir in the addback water. The goal is to bring the reservoir back up to 1300ppm. In this strategy, I feel a single res change at harvest is sufficient.
Despite the obvious concern that this non dumping approach allows toxins to build up, I never experienced toxin buildup. this surprised me and caused me to alter my thinking about plant metabolism. It seems they do not excrete toxins the way organisms with digestive tracts do.
How much nutes goes in the addback water varies by res to light ratio. For example, a 50 gallon res under a single 1k can be topped with 33% of 0-8-16, and the 1300 tds will be approximately achieved... Im not a stickler for that number, and am happy fluctuating anywhere between 1100 and 1500ppm over the course of a week, such that if one chooses to top only with water for a few days, the nuteing can be done in a single session each week.
If the same 50 gallon res is used under twice as much light, it will probably require twice as much nutes in the addback water.
The most primary concern is to achieve the TDS increase, while staying within pH range
adding nutes lowers pH, so sometimes one can avoid pH adjusting, by adding more or less nutes
adding water raises pH, so dont adjust a reservoir, until it is topped up with water and nutes
> What size trays would you suggest?
I think in terms of 4x4 footprint per 1k, although with high plant numbers, it can work with 3x3 footprint
so for a 2k project, either a 4x8 or 3x6 table
plant numbers vary by veg time. with 3 weeks of veg (counting starts the day rooted clones are transplanted), 10-12 plants per 1k is enough. With 1 week of veg 30-40 plants per 1k is enough.
disclaimer, plant numbers increase legal penalties. I do not encourage you to break the law, you should only use my advice if you are a qualified patient and are able to cultivate legally. However, even then, Federal Law still makes cultivation in the US illegal. Dont break the law on my advice.
The suggested amount of medium per 1k is 30-50 gal, so 10 three gallon pots is the same total as 30 one gallon pots
> What media would you recommend- corn, coir/perlite, rockwool, etc…?
As a hydroponics medium, I prefer clay balls
other denser mediums work if they are not overwatered
> As a corollary: if rockwool is an option, what size cubes will produce the most productive results?
Other than cloning in a dome, I have no positive experience with rockwool in larger blocks. It usually succcumbs to algae, which is a breeding zone for many problems. I do not recommend blooming in rockwool. But Im sure there are others with more experience than I have working with it, that can contribute their safe operations parameters.
thanks for your kind words, and for giving me a forum for my opinions
> I was wondering what your current thoughts and opinions are in regards to changing out your reservoir? Should I bother changing it out? Or not...? Is the 5 ml, and 8 ml of Flora Nova Bloom still the standard when it comes to veg and flower?
I dont think it is necessary to change out the reservoir until harvest. But it should be kept full, so the nutes dont get too concentrated. I dont have a weaker formula for veg.. The only time I use weaker nutes is under fluorescent lights.
I did at one time create a complex mathematical formula to predict how much nutes you need to addback for a given res TDS. But rather than recreate it, I invite someone to post it.
The main concept is to bring the TDS back to 1300-1400.
Here is a practical example.
Imagine a 1k light with a 50 gallon res, starting at 1300ppm. The nute is FloraNovaBloom in RO water @ 8ml per gallon, plus about 1-2ml of pH UP per gallon.. depending on the type of pH UP you use... I think Earth Juice Natural pH UP works fine, so does GH brand pH UP
Each day for 6 days the res is topped up with plain RO water. After adding the water, a TDS reading is taken. If its more than 1100, dont bother adding nutes unless you like the task. (how fast the TDS drops depends on how big the plants are, just focus on the TDS number, not the number of days in this example)
On day 7 a TDS reading shows 1000 ppm, so a guesstimate is made that 2ml/ the 50 gallons res size (thats a little less than 33%) , might bring the TDS back to 1300.
So the gardener puts 100ml of Flora Nova Bloom into the res, waits a few minutes for stirring, and does a TDS reading.
If it comes out to more than 1300, then the operator uses less than 100mls the next time TDS drops to 1000
soon a pattern will emerge, and nutes dosing becomes predictable, both for pH and TDS