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Hello all Growers, Hope you are all well. I did an experiment today and found out something quite interesting. Yes it is a lock down experiment I am mainly an indoor grower but all my Sarracenia, VFT and Darlingtonia are all outside and watered with rain water. I live in the North West of England. I grow three hybrids of Nepenthes in a window, a few Drosera binata in a window, a Ping in a window and a hell of a lot of Cephalotus in windows. I went peat free about three years ago. I straight switched coir for peat but always noticed a definite sulk in all my plants on re-potting. I have an eBay (£3) TDS meter and to the 10's they are quite sufficient. I have a eBay Reverse Osmosis (RO) unit I bought for about £35 and my RO water goes from tap (@360 ppm) to 15-10 ppm depending on the time of year. Well below the magical figure of 50 ppm. No one has died! I hydrated a whole brick of Coir at the recommended rate using water at 11 ppm (yesterday) from my eBay RO unit. I left it for one day to fully hydrate. After that I put 125 g of coir in a 3.5 inch pot with a disc of clean J-Cloth at the bottom. This is about 250 mL in volume to the brim. I then poured a series of 125 g of water (125mL) over the pot and collected the effluent (what came out the bottom of the pot) over 10 minutes. Of interest was that the volume of the first effluent was only 40 mLs! After that the effluent matched just under what I put in. This suggests that the compost was not fully hydrated originally? Bottom line was that I washed a mass of 125 g of coir with a mass of 125 g of water 10 times and waited 10 minutes to collect the water that passed through that compost. I measured the TDS of each washout. Here are the results: Wash 1 - 907 ppm Wash 2 - 600 ppm Wash 3 - 229 ppm Wash 4 - 101 ppm Wash 5 - 50 ppm Wash 6 - 33 ppm Wash 7 - 27 ppm Wash 8 - 25 ppm Wash 9 -22 ppm Wash 10 - 21 ppm Considering I was washing with water at TDS 11 ppm, it took me two washes to get washout less than my tap water! It took five washes to get to the "magic" level of less that 50 ppm much after wash 6 there is no improvement. I may repeat this experiment with water at 0 TDS? Take 11 of the figures. Bottom line is wash your coir and wash it at least five times. After that it is fine. I have VFTs, Cephs, Sarrs in it but I kind of noticed the water in the trays going up when I first started using it and I just flushed the pots through a couple of times with rainwater. TDS goes up with passage through peat too (a bit). I suggest the first wash of your coir is using tap water! Keep safe, and as Jeff and Dallas say... Happy Growing! Peace Adam x
I've been using the same old bag of peat moss since starting the hobby. But last week it ran out just before I got in an order of Plants... So based on advice seen on this forum I went out and got Shamrock branded peat, but I now think I've done something wrong, like get the wrong bag or something. My plants arrived in the post this morning and were all potted up and stuck in a terrarium with high humidity (instead of using a bag) and they all got top watered. But out of curiosity I checked the TDS of the water that collected in the bottom of the terrarium and it had gone from 7ppm to 62ppm. So I'm just wondering is this normal for peat to change the water parameters so much? Could it be the sphagnum, sand or perlite doing this? Have I bought the wrong peat, it says all natural on the bad(picture of bag below)? If this is normal should I just keep watering until the parameters come back within 30ppm?
I'd like to pin down once and for all the infomation I'm picking up from the net about watering carnivorous plants with tap water. While I know it is bad for them and I still use filtered rain water for mine I have seen advice ranging from "It is ok now and again" to "YOU WILL TEAR APART THE FABRIC OF SPACE TIME IF YOU DO" well not that bad but have seen "Even a drop is a 100% kill for CP's". I know there are fancy filters on the market and such and even people saying to use deionised water (the type for car batteries and irons) at a push if stuck. But is tap water as a one off really that bad?