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Aquarium salt is widely used to help prevent illness as well as treating for different diseases. Salts are widely used because they have so many benefits compared to using medications.
Examples:
Before using salt you will want to remove submerged plants and perform a water change of 50%.
Salts that can be used are:
Below is a helpful chart to use when help is needed!
However, the recommended dosage from Doc Johnson is 1 teaspoon of salt per gallon of water every 12 hours not to exceed 3 treatments. If dealing with large tanks or ponds you will need to use 3 pounds of salt per 100 gallons of water.
Also read the information below:
Salt levels do not dissipate with water evaporation or small water changes. Freshwater/coldwater fish like Goldfish are not designed to live in a saline environment. Salt is a wonderful remedy to treat ailments, or to control the toxicity of nitrite/nitrate spikes, but as a normal maintenance procedure it is a no-no for goldfish. Salt also tends to make water harder. If you already have hard water, you are adding to his stress. Through what is called "osmosis" your goldfish already maintains a normal high salt concentration in his body fluids and needs to absorb freshwater into his cells to keep in balance. By adding more salt to his water, you are overloading his system and putting him under osmotic stress. This can be fatal. It saps their energy and strength and weakens their immune system, or can even kill them. This is probably why your fish is spending a lot of time "sleeping" at the bottom of the tank. Give him some fresh oxygenated water w/o the salt. Save the salt for only when he is sick or there is a problem with your water. Happy fishing!!
Salt Dips
Low Salt Dosages
Chart taken from A Fishkeeper's Guide to The Healthy Aquarium
Aquarium Pharmaceuticals Pond Salt
All-natural salt provides essential electrolytes fish need to survive. Made from evaporated sea water.
Aquarium Pharmaceuticals Aquarium Salt
The proper use of this all natural Aquarium Salt can reduce fish stress, add natural electrolytes and improve gill function.