Baking Soda Method You can also effectively raise pH levels using sodium bicarbonate, also known as baking soda. But, how much baking soda should you add to your pond to raise pH levels? As a rule of thumb, start with 1 tsp for every 10 gallons of pond water.Click to see full answer. Then, what Causes Low Pond pH?On the other hand, low ph is usually caused by organic life in the pond. The carbon dioxide then forms carbonic acid which in turn lowers the ph. The fish also give off carbon dioxide which also quickly converts to carbonic acid thus adding to the ph lowering.Beside above, what should the pH of pond water be? The proper pH of pond water with fish is from 6.5 to 8.5. Pond fish have an average blood pH of 7.4 (pH is a measure of water’s acidity or alkalinity). The closer your pond pH is to 7.4 the better. Outside of the 6.5-8.5 pH range your fish can stress out and weaken their immune system. Similarly, how do I raise the pH level in my pond? If your pond experiences a pH crash, meaning the pH dives below 6.5 you can use baking soda at a rate of 1 teaspoon for every 5-10 gallons of pond water. Best practice is to collect some pond water in a bucket and dissolve the recommended amount of baking soda for your pond in the bucket.How much baking soda does it take to raise pH in a pond?We recommend adding 1 cup of baking soda per 1,000 gallons of pond water daily until your KH level has increased to 150 PPM.