Benzelsanswered grow question 3 years ago It depends on the water conditioner- but generally speaking- no. Tap water conditioners work by neutralizing the chlorine that’s contained in the water through the formation of ionic bonds that render the chlorine harmless. Explained simply, the water conditioner acts like a magnet, drawing the chlorine molecules away from your fishes’ sensitive gills and making the water safe for use in your fish tank.
However, if the water contains chloramine as well as chlorine, you’ll need to use a conditioner that can split the ammonia/chlorine bond and deal with each individually. To complicate matters, many water companies habitually switch between using chlorine and chloramine. So, it’s safest to use a tap water conditioner that deals with both. Chloramine also doesnt evaporate like chlorine does if left standing, its much more stable so depending on temp of water, it may need to be left standing for up to two weeks....or even boiled if temps are like winter freezing temps as if its too cold u can leave it standing for a month and it will still be present. Check with your water company directly to find out if its present in your water- it most certainly is in mine, and in higher amounts than many of us here would like.
So heres your issue- the conditioner you have may not even do the job you want it to, depending on whats in your water, as well as water conditioners do the same thing to heavy metals as well as ammonia - and your plants actually need these metals in trace amounts and ammonia breaks down into nitrogen, in fact many veg nutes use ammonium nitrate for this reason, and in the bloom nutes they switch to potassium nitrate. Certain water conditioners will also bind to Nitrate's and Nitrite's therefore making your nutes less effective or useless even.
I ran 19 aquariums at one at one point, even had em set u outside as I ran out of room in the house. So dont use water conditioners in plant water ok?