4 dKH Lab Certified Analytical Standard - 118ml
4° KH or 4 dKH LAB CERTIFIED ANALYTICAL STANDARD - 118ml (4 oz) bottle
CO2 Level Indicator Fluid: 71.44ppm Alkalinity as CaCO3
* ships with / includes pipette for ease of filling drop checker with indicator fluid
4 dKH fluid is used in a CO2 drop checker as a CO2 level indicator. When combined with pH reagent, the solution color will change from blue to green when optimal CO2 of 30ppm is achieved.KH Standard / 4 dKH (lab certified analytical standard 4 dKH) is used in the drop checker to accurately measure CO2 levels in the aquarium. The KH standard / 4 dKH needs to be combined with approximately 2 - 4 drops of pH indicator in your drop checker until a strong transparent blue color is achieved.
Instructions for Use of 4 dKH in CO2 Drop Checker
Combine bromothymol blue/pH indicator reagent into 4 dKH fluid in your CO2 checker until a strong blue color is reached. Install checker on tank and wait 2 hours to observe color change/CO2 reading.
Drop Checker Color Chart of Aquarium CO2 Level
BLUE ... low level of CO2 <30ppm ... increase rate of CO2
GREEN ... proper CO2 level of 30ppm ... no action required
YELLOW ... high level of CO2 >30ppm ... decrease rate of CO2
*all color observations & CO2 adjustments require 2 hours wait period for accurate color readings.
*use 4dKH with drops of bromothymol blue/pH reagent to create DIY Indicator Fluid for CaL Aqua Labs CO2 checker glassware