i would not guess at that without a ppm meter but if you are using 20 gallons of water follow the directions on the bottles but only mix it for like 16 or 18 gallons to be safe till your ppm shows up:mrgreen:
drain and start with fresh water when i switch then again this time i did not just to see what would happen and i started slow and worked up seems ok 5 weeks into flowering and it looks great never changed water at all maybe luck but i will see next time as i will do this again.
i use this gh and for grow i start out at 1100 ppm for the first week or 2 then in 3 and 4 up to 1600ppm and in flowering started at 1100 and by the 6 and 7th week i up to 2000-2100 ppm and it is in recirc dwc:blsmoke:
i will take some pics for ya of my hard water i use just ph'd down to 6 and res temp of 64 . my ppm of the water out of the tap andit is well water with uv filtration is 386 +-15
4 weeks into flowering they are 4.5'
mine is a small setup as i have no room i have moved the nute levels alot higher then half now that i am used to hydro now just did not want any mess ups right away i pretty much go by the nutes directions and just subtract 2 gallons and never had any probs gives me a little leeway either way.i...
start slow with a ton of reading and asking questions. then figure your space and build start small and build from there this way when everything hits the fan not such a loss.i built mine for wwwwaaaaayyyyy less than that and i have fans ducting arbon scrubber hydro pumps the stuff you really...
silk you also could use a ro-di system for your water i do for my saltwater fish tank and it takes the minerals out ppm at 390 and with ro ppm 008 so that is anothe option as well
well i use 16ltr pails i used 1" pvc bulkhead fittings for the drains then put a union at each bucket a few tee's and elbows and out of the closet and into the res. then i plumbed the the water in with half inch pvc. everything is glued and no leaks thats a +.the water intake lines have unions...
the half is more theory worked for me and never had a burnt plant yet. then i just move ppm up from there was a base line because i have never done hydro before and wanted no problems thats how i started with soil and worked my way up till i new my limits. i think in the whole time of growing...
never had that prob but i went with 1 inch drains and all the plumbing is pvc. was always worried about leaks and over flowing who needs that right. maybe i went overboard but no leaks no clogging no probs i even have auto top off rigged up on it . everything works a okay this is the third time...
i have very hard water myself and switched to dwc from soil and i have been having no probs what so ever. i have done a ton of reading and was worried as well but seems to me i worried for no reason i am using gh nova series nutes on this grow and on the previous one i used bumper crop ab...