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Product description

Aquarium CO2 Drop Checker Solution 15ml. 

It consists of a pre-made 4dKH solution containing the appropriate amount of reagent. No mixing nor preparation is needed for its easy use. Simply open the bottle and fill the CO2 drop checker.

  1. Fill the drop checker 2/3 full of CO2 Drop Checker Solution (about 25/30drops)
  2. Now invert it, being careful not to spill the fluid 
  3. Next, holding it level, mount the checker anywhere on the front glass inside the tank so that air is trapped in the vessel
  4. When the reagent solution is deep green, the optimum amount of CO2 is diluted in the water column
  5. Replace CO2 Drop Checker Solution minimum once a month to maintain an accurate read.

When the drop checker is submerged in the aquarium, the carbon dioxide in the water will fill the airspace of the drop checker and will eventually be absorbed into the indicator solution. The carbon dioxide will seek a point of equilibrium between the indicator solution and the aquarium water. As equilibrium is achieved, the color of the indicator solution inside of the drop checker will change based on the concentration of CO2 in the water column.

If the indicator solution is deep green in color, then appropriate levels of carbon dioxide are present in the aquarium and no action is required. If the solution changes to blue or yellow, then the CO2 levels are too low or too high, respectively. When the reagent turns yellowish, your livestock can be in danger as too much CO2 is lethal to fish. 

Drop Checker Kit installation tutorial:

https://www.youtube.com/watch?v=XwOZ2tePnRc

Shipping and delivery

Free delivery on orders over $70; otherwise $14.99 in the US and $24.99 for the rest of the world. Orders placed before 2 PM CET are usually processed the same day — a regulator may need a little longer, because every one is assembled and tested before it ships. Delivery is fully tracked: 2–5 business days in the US. Customs or import duties outside the US are charged on arrival. Shipping & returns

Warranty and lifetime support

The Advance Professional and Professional dual-stage regulators carry a warranty of up to 10 years; every other CO2Art product carries the standard 2-year manufacturer's warranty. All customers receive lifetime free online technical support. Warranty terms

Satisfaction guarantee

If you are not satisfied with the quality of a product within 30 days of purchase, we send a full refund or a replacement at no charge. Mechanical defects found during the first year are repaired, with any parts needed, at no cost to you. The guarantee