Topping up a DWC Res

[Gjohnstone]

Hello, I have been testing my ppm’s as my res needs water in my DWC buckets. The PPM stays very consistent even as the water drops a litre or two so I have been topping up with mainly water. What does everyone do? Mix in a lite amount of nutrients?

[9fingerleafs]

i dont know what people do because i grow in coco but i can tell you its a great sign that ppms stay put, believe me you dont want the problems of too high or too low ec, if you need to top your reservoir every liter or two then you are going to have to mix every liter or two

[gbauto]

If your ppm's are steady as your levels drop it means that your base concentration is perfect so add the same back in(use mixed solution).

[HappyDaze]

And you can do the same thing if nutes are concentrating or dropping between top ups with an add back program. You want to add a proportionately more concentrated nutrient solution when you're topping a rez where the PPMs are dropping and a less concentrated solution when PPMs are rising.

I'm still experimenting, I'd like to get to a point where only four complete rez changes are required. First change 3 weeks into veg, second on 12/12 flip, third mid flower, last one to flush during the last week.

[DW2]

Howdy Gjohnstone, When I top off the reservoirs in my DWC (Bubbleponic set ups), I add only plain pH'ed water (around 6.0). I would think tat if the PPM staying the same, would indicate that the plants were taking up the nutrients and the water at a 'normal' rate. The PPM is, more or less, a measure of concentration of the dissolved minerals in the water. If the PPM was to go up a great amount, I would think that it would be an indication of 'nutrient lock out' and would be something to be concerned about.

[HappyDaze]

If the plant is drinking more than it's consuming in nutrients, it could mean the concentration was too high to start with....not necessarily "lockout".

[RFheavy]

I always bring two milk jugs with me. One with just water, and the other with my nutrient/water mix. Depending on where my ppm is at, I'll add more water than nute mix(or vice versa). I'm always using both jugs unless I need to amp up the ppm or reduce them significantly.

[9fingerleafs]

thats a smart way to go

[RFheavy]

Thanks! It seems like more work at first, but once you get the hang of it, you can eyeball pour pretty consistently to achieve desired levels.

[RagWeedDWC]

I do about the same, measure then pour what's needed. My gut has always been that it should be consistent or as was stated before, your over or under feeding.