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Why worry about chlorine? Experts say .05 parts per million (ppm) of chlorine in your pond can result in fish deaths. Others say, you can add 10% chlorinated water to your pond without any worries. Guess what? If your chlorinated water has 0.5 ppm, a typical value, and you add 10% to your pond, the pond concentration of chlorine is .05 ppm - a toxic level!

Sodium thiosulfate instantaneously removes chlorine. However, some commercial preparations give incorrect dosage calculations for its use. Following these directions can result in large residual concentrations of Sodium thiosulfate over time that can approach toxic levels to your fish.

Additionally large residual concentrations of Sodium thiosulfate can interfere with Potassium permanganate and other treatments.

The chemical reaction for the removal of chlorine by sodium thiosulfate pentahydrate is as follows:

2 Na2S2O3 (5 H2O) + Cl2 = 2 NaCl + Na2S4O6 = salt + sodium dithionate

In order to properly treat the amount of chlorinated water added to your pond you need to make several calculations:

  1. What is the concentration of chlorine in your city water in parts per million (ppm)?
  2. How many gallons are you going to add?
  3. What form is your sodium thiosulfate in?
  4. What is the purity of your sodium thiosulfate?

If you want to simplify this process, we have developed a very easy method to add chlorinated water with your garden hose, without any calculations! You don't even need to know how many gallons you add.

We sell a device that connects to your hose, with a siphon attachment that drops into another container. You simply mix the solution for the siphon container according to our directions, test its performance, and then turn your hose on into your pond until the desired pond level is safely reached.

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To order this device simply fill out the following form and click the submit button!

Order Form

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Siphoner @ $19.95 quantity

Sodium thiosulfate pentahydrate @ $9.95 quantity

Orders subject to customary shipping and handling charges

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