NaCl (sodium chloride) not MARINE SALT (it has buffers that are harmful to many freshwater fish).
"Sea salt" is good for cooking and a foot soak but not for fish, as it is formed (evaporation ponds) it undergoes to many irreversible changes.
Prevents nitrIte/nitrAte poisoning (in proper concentrations) with new setups.
Prevents parasite growth & infestation by interfering with the life cycle (like Chilodonella cyprini), Costia infestations.
Lowers osmotic pressure.
Adds electrolytes (this is where the gill thing comes in, osmoregulatory stress).
Replaces sodium and chloride ions that fish need.
Raises the Hardness (gH) not good for true softwater fish (ie hatchetfish, elephantnoses, discus, neon tetras, cardinal tetras, rummy nose tetras, corys, discus) angelfish can tolerate it some.
Some livebearers & some [FONT=Arial,Helvetica]cichlids [/FONT](originally brackish or enter brackish water) can benifit if you hard hard water.
Know the salinity for your tap water, don't add salt until you do.
Don't use in planted tanks and with scaleless fish.
Care should be taken asit acts as an irritant to goldfish, & koi.
Don't use with Zeolite, as it stops it from removing ammonia/ammonium.
You must thoroughly dissolve & dilute the salt before adding it to the tank water. (it can chemically burn the fish).
Too much salt causes bloat.
The Iodine in table salt is inconsequential (fish would be pickled before being killed by the Iodine). Fish can develop goiter in captivity from the lack of iodine. Decaking agents are in such low quantities they are not a problem either.
Remember that salt does not evaporate. Add one and test accordingly before addition of any more.
Salt has it's place in fish hubandry, mostly as a tonic or treatment, but you should be fairly well versed before using it or follow directions from someone who is.
Dr Joe
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