OP OP anewbie Fish Herder Fish of the Month 🌟 Joined May 30, 2021 Messages 1,619 Reaction score 1,398 Location usa Today at 1:34 PM #46 gwand said: Beautiful. What does ec 21 stand for? Click to expand... conductivity. Nearly all tds pens are really just ec pens - so this is sort of like a tds of 10 1/2. Very soft water.
gwand said: Beautiful. What does ec 21 stand for? Click to expand... conductivity. Nearly all tds pens are really just ec pens - so this is sort of like a tds of 10 1/2. Very soft water.