I'm growing in a DWC system and using EC meter. It looks like there's quite a lot of salt buildup happening in the weeks of flowering. I have quite big tanks so I don't need a reservoir. How do people here deal with salt buildup. Do I need to change the solution every week or can I put something into the system that prevents the salt buildup?
Clearex Clearex 32oz [32oz] - $12.95 : neHydro.com, Hydroponics and Gardening Supplies The link is just the closest I could find, you could buy it in alot of places. Just follow the directions on the bottle for DWC type systems.
Clearex works well for flushing the system of nutrient salts but not to be used ialong with your nutrient regimen. You will potentially need less flushes and have less build-ups if you use Drip Clean in addition to your nutrients and follow this guide to dial-in the strength of your nutrient solution: The Doc's Prescription for DWC
Who are you talking to. Well no one here say's he's swapping solution every 7 - 10 days. I asked the question if I needed to do that to prevent salt build up. But I guess I'm using a bit too much nutes.
Are you having some crusty stuff build up on your media? That happen to a friend running a wicking system. Never heard of it in DWC tho ....
Just flushed mine (DWC) With Clearex for 1 hr as instructed. I was having rapid daily decline in ph which my local hydro guy attributed to salt build up. We shall see...
Wow, it is shocking that so many responded with an opinion but no one even come close to addressing your question except for Tihspeed.. Raoul is right too.. Salt buildup on the grow medium of a DWC system really should not happen because the nutrients should not be that high to touch the grow medium (which I assume is hydroton within a net cup).. The water level should be about an inch or so below the net cups, so the water (outside of some light splashing from the bubbles) should never really come in contact with the grow medium for salts to build up on it.. Do NOT use Clearex unless you're in the last week of flower.. You never said what your ec/ppm was which you're running.. In any case, your guess and Tihspeed are correct, lower your ppm.. To get most of the salt buildup off the medium, you can simply pour some pHed water over the grow medium and then I also would advise you change the nutrients every week..
Clearex bottle says to use every couple water changes to control salt buildup...just sayin...this would not comport with just before harvest only. However, it also says that it helps induce the final reproductive stage. This stuff is just like construction, you get different advise from different people. Notice, I did not say to do it. I said I did it. And I'm pissed that I did because it cost me $15 and I got more input which suggests that my ph is dropping because my nutes are too high. When you say "It looks like there's quite a lot of salt buildup happening" what do you mean "looks?" Is there visable crust build up inside the tank? RU having symptoms, or just a crusty appearance?
It seems possible that Clearex might facilitate the final stage of bloom once the plant is at that point, but I'm not sure it would induce the plant to advance/accelerate into an end stage that it was not genetically/developmentally ready for. IOW, once the plant is at the end stage of bloom it might enhance the process with a flush even while nutes are still being used on a dialy basis.
Clearex, Final Phase, FloraKleen, etc. etc. etc. etc. These are flushing formulas that generally consist of chemicals which pull or strip residues out of your plants for a final flush of the plant before harvest. Of course Clearex is going to say use it every couple changes, how can they sell the product if they say only use 100mL once in 8-10 weeks... Just like GH says use FloraShield in every reservoir change, WRONG... Of course they have to promote the product's safe to use "all the time" or they would never sell it....
Unless the market for this product, and it's "sales driven" instructions (as presently written) is mostly supported by vulnerable newbies, the free market would have driven the manufacturer to adjust their instructions after the customer realizes that they have been bullshitted into harming their plants. If this product induces an end to ones bloom phase early, people will easily notice and be pissed-forcing a legit company to change their label, or, watch their entire customer base erode. They also bullshitted my vendor, or, perhaps he's in on it. He would rather fuck me over and make a dollar than see my crop succeed. Or, at worst it is a waste, but without harm. He described a test he did where salts were sprayed with straight water and Clearex, and the difference was vast. The bottom line, beyond my speculation as a newbie, what ill effect has "salt flushing" as instructed had on peoples plants? Once a month, rather than every other water change, may be more to your point. Remember also, the salt flush instruction is for 15 min to one hour added to water as you watch your ppm meter rise and eventually stop, not for days, as I understand it to be the case with a end bloom flush.
Of course product labels are mostly sales driven.. But why would you want to use a chemical (which is absorbed by your plant, that you smoke) to remove salts when plain old water is a great solvent for salts.. You see, when an ionic or polar compound enters water, it is surrounded by the water molecules. The relatively small size of water molecules typically allows many water molecules to surround one molecule of solute. The partially negative dipoles of the water are attracted to positively charged components of the solute, and vice versa for the positive dipoles. In general, ionic and polar substances such as acids, alcohols, and salts are easily soluble in water, and nonpolar substances such as fats and oils are not. Nonpolar molecules stay together in water because it is energetically more favorable for the water molecules to hydrogen bond to each other than to engage in interactions with nonpolar molecules. Here is a little read from bioinquiry.biol.vt.edu about how and why water is one of the best solvents for salts... There are other laboratories which have conducted studies on water being used as a solvent for ionic and polar substances.. Just a quick search I found this site which maybe can help you better understand how and why... The Interactive Library.
Sorry, I'm high as shit right now and lost my train of thought getting all technical... LOL If you want to flush your grow medium of salts, just take a gallon or so of pHed water and pour it through your grow medium then change your reservoir with fresh nutrients... Now guess how much that cost me to flush the salts from my grow medium...
Given your tech/bio input im inclined to defer to your view. Your inital email was dominated by a market conspiricy, which i am always very skepticle of. Fancy a bit of input on why straight phed water is not the prefered method also for final flush?
It is in my garden... But let me ask you this, does salt break down and dissolve in water??? Why would I need a chemical to dissolve salt??? A lot of growers say the need to "final" flush is bullshit.. They say that ALL you're doing is robbing the plants of their nutrients in the last week of growing during the period of most resin production... To each is his or her own.. I'm ALWAYS a skeptical about marketing and believe if companies told the truth as it is, as opposed to stretching the truth a little to get their product sold and boost their shareholder's revenues, they would not sell as much of their products..
curious, what is the argument for chemical flush at final bloom? Last, he said he does see deposits...as illogical as that may be given a dwc, it seems the salts are residue from the nutes..probably too high nutes...so flush w/h20 and lower nutes?
No arguing here dude... Just having a discussing with you, because Tihspeed answered his question long ago... I'm sorry dude, but IMO threads where this kind of shit is discussed are some of the best information and what make up a great forum...