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Co2

CO2 Drop Checker

A glass indicator that visually shows dissolved CO2 levels in a planted tank via colour change.

Price: Budget For: Freshwater Essential gear $10-$40

📖 Overview

A small suspended glass chamber filled with 4dKH reference solution and bromothymol blue indicator. Blue = low CO2, green = ideal (~30 ppm), yellow = dangerously high. The essential tool for tuning pressurised CO2 injection.

🛒 Buying Guide

pH controllers offer more precise measurement but drop checkers give reliable visual feedback at low cost.