Regarding how often to change the res, it seems like most growers change their reservoir either weekly or biweekly. The people who make a living selling nutrients do you tend to tell you that you should change your reservoir every week. Given that those people will only have a job if you buy nutrients, it's not unexpected that they will tend to recommend that you change the reservoir more frequently than if they had no vested interest.
Is weekly the right answer? In a lot of situations, it probably is. In this grow, the reservoir is 4 gallons and plants are starting to grow quickly so it's reasonable and prudent to assume that the intermediate uptake nutrients will be depleted fairly quickly. I would be inclined to err on the side of caution and swap the res weekly but also accept that there won't necessarily be any harm if you wait 10 days or 2 weeks between changes. It really does depend on the grower and the grow.
One video that I watched on this topic is on the Jack's nutrients website. When the question "How often should we swap our res?" comes up, I think there were three growers who gave opinions. One said, essentially, that he changes the res every week and the other two said "Well we sort of get around to it maybe every other week and sometimes it goes a month." That's from the people who manufacture nutrients!
I've read postings from growers who use one res for veg, topping up with diluted nutes, and then a fresh res in flower, again only topping up. That seems extreme to me but the growers who follow that practice have a lot of years of experience and are getting good results.
Per my previous posting, I'm going to go through the Bugbee article and see if I can figure out a valid "refill solution" for my nutes (I use the Jacks "3-2-1" formula in a 3.8-2.5-0 formulation) and use that during my next grow.
Is weekly the right answer? In a lot of situations, it probably is. In this grow, the reservoir is 4 gallons and plants are starting to grow quickly so it's reasonable and prudent to assume that the intermediate uptake nutrients will be depleted fairly quickly. I would be inclined to err on the side of caution and swap the res weekly but also accept that there won't necessarily be any harm if you wait 10 days or 2 weeks between changes. It really does depend on the grower and the grow.
One video that I watched on this topic is on the Jack's nutrients website. When the question "How often should we swap our res?" comes up, I think there were three growers who gave opinions. One said, essentially, that he changes the res every week and the other two said "Well we sort of get around to it maybe every other week and sometimes it goes a month." That's from the people who manufacture nutrients!
I've read postings from growers who use one res for veg, topping up with diluted nutes, and then a fresh res in flower, again only topping up. That seems extreme to me but the growers who follow that practice have a lot of years of experience and are getting good results.
Per my previous posting, I'm going to go through the Bugbee article and see if I can figure out a valid "refill solution" for my nutes (I use the Jacks "3-2-1" formula in a 3.8-2.5-0 formulation) and use that during my next grow.