True tds or ppm

Do you need to subtract the ppm of the water in order to get nutrient ppm correct

Yes water strait number subtracted from your mix 200 water 1200 would be 1000ppm nutes

Thanks. You know I have 1000 watt light,and I’ve read where CO2 emitted into growroom is almost needed for better yield.So I got a CO2 meter ordered, but what might be the best way to add CO2 a metered bottle, or just one of those bags?

CO2 isn’t worth the effort for the average grower. Ambient CO2 PPM often runs somewhere between 400 and 800 PPM and it is sufficient for healthy plants/flowers and a productive yield. The reason that it isn’t worth the cost and effort is that it requires very high light intensity (A 1,000 watt light won’t get it done if it is a burple,) high temps, and high nutrient loads for supplemental CO2 to make a difference.


Still have to count the initial input TDS and is additive. In other words if your target schedule calls for 1,000 ppm and your tap is 200, correct mix would be 800 ppm salts and 200 ppm tap for 1,000 total.

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I dont because every point in tap water is not gaurnteed to br calcium rust ammonia fluoride cholrine boron… Well water can be 350+ ro is 50 or less how can 1000 starting at 350 being only 650 aditional apposed to 950 in ro… nute ppms inputs will be way diff… When my nute program says 2 ml 2 ml 5 nl 8ml 10ml. I dont adjust that to my water