tap water ppm q's

[xcrispi]

hey folks ppm q's for ya .
been at this a lil while w/o probs. but i'm curious , our tap wtr is 80 ppm. if i mix my nutes to be lets say 1000ppm. should i make it 1080ppm. because of ppm. of plain tap water ?:confused:
thanx in advance n peace
:thumbsup:

[GluteusMaximus]

Yes, that's exactly what you should do.

When you mix fertilizers to the value you set or are targetting, you must adjust for all the non-fertilizer ingredients. One way to do this is to add your supliments to the reservoir water prior to adding fertilizers. Take the TDS reading from that mixture and add that to your target fertilizer TDS.

Using your example.....Your ending PPM should be your target fertilizer PPM (1000ppm)+ beginning tap water (80ppm) + any supliments ppm.

Something to remember. Don't max out your fertilizer PPM and assume any additional TDS inside your reservoir is harmless. You have a maximum TDS (of all ingredients) that must not be exceeded.

[xcrispi]

sweet ,
thanx for quick reply .
G/B
peace

[monty5309]

My water is about 140 ppm @ 7.5 pH coming out of the tap, so I add enough Calcium to bring it up to 300 ppm then adj nutes for approx 1000 ppm/5.5 - 5.9 pH. When rooting and early veg, they seem to do better on the acidic end around 5.3 to 5.5 pH then around 5.5 to 5.8 pH for bloom...

[monty5309]

Your nutes will vary by as much as 200 ppm when the water evaporates and the plants feed. As water level goes way down, the nute level will go way up (1200-1400 ppm) & pH up also. Just add water (no nutes) to reservoir after you have added carbs, B1, Pro Silicate, SM-90, etc & adj pH to 5.8