Salt!

[YoFishboy]

The negative long term effects are related to increased TDS for fish which can adapt to higher TDS water without difficulty short-term, but it is extra metabolic work for them long-term, coupled with the major difficulty of measuring NaCl in FW at relatively low concentrations. You have no easy test other than TDS for what your water is doing, as it shows not at all on the standard hobby tests.

There are many fish which are highly succeptible to Ich, mollies are just one (Clown loaches are the most IME, followed by Tiger Barbs).

There is no justification for using salt for high-nitrate water changes. In OTS situations, care is needed to avoid osmotic shock, but substituting salt as an unmeasurable osmotic agent is not just poor, it is potentially every bit as damaging as the OTS situation and quite similar to it.

Humans cannot taste salt in water below low brackish concentrations. The implication that the lack our ability to detect the salt means it would be harmless to the fish is also absurd, totally without rational basis. We cannot taste puffer toxin either, that in no way means that it is harmless.

The statement that salt improves gill function is also without basis.

The statement that salt improves the efficacy of meds is equally absurd. Any statement of that broad nature is highly suspect.

In short, that poster was posing as someone with knowledge of physiology and pharmacolgy which is, on the face of it, simply without any basis in fact.

That is not an uncommon situation, but is a sad one.

uh...DITTO!..er ..what he said..right...what the hell does this guy do any way? He even alpha-numerically lists his tanks..oh wait..he is..an analyst....I understand now.....Hehe! ...just kidden....your tank set up is amazing (and very neat..hehe)...and the planted tanks are the nicest I've ever seen....that's one of the tank realms I haven't explored much...yet......and yes, clown loaches come "salted" with ich automatically it seems...parden the pun...Now....time to plan....daughter off to college in 2 years...I must begin plans to invade and take over her room for fish so I can have a set up like RTR's!

 

[Raskolnikov]

Most of the salt/no salt arguments that stem here and elsewhere seem plagued by the same problems over and over again. Person A kept their fishes with added NaCl for years, and Person B kept their fishes for years without adding any. This doesn't make a case for or against the addition of NaCl to aquarium water.

One problem with any blanket statements regarding fish keeping in general is the tremendous diversity of fishes. Genetically, one can find more similarities between a squirrel and a turtle, than exist in two organisms that can both be referred to as a "fish" though both fishes may look more superficially similar.

So back to salt, and more generalities. Stenohaline fishes are intolerant to changes in the concentration of salts in the surrounding water, be it an increase or decrease of salinity. More fish fall into the general category of euryhaline, that is they can tolerate swings in salinity so long as they aren't too extreme and don't occur too quickly. (Though there are fishes that deal just fine with continued rapid changes in salinity, but we'll consider them an exception at this point in time.)

Chloride cells, located most prevailantly on the gills of bony fishes, are responsible for ion exchange (for the purpose of this conversation, this is the ability to maintain concentrations of ions [like Na+ and Cl-] in relative constants within the fish by drawing in or discharging said ions). Most fishes are well prepared to live within varying levels of salinity, within reason. Furthermore, some fishes such as guppies and tilapia, have been shown to change the number of these chloride cell complexes (increasing or decreasing them) depending on the gradually changing salinity of the water in which they've been kept. Many fishes have the ability to tolerate a variety of stable salinities. I don't add salt to my tap water in order to keep fish in it. Tap water already has more than enough sodium and chloride ions to support freshwater fish functions, so it's unneccessary to do so.


So what's the point of this? A fish is not a fish is not a fish. With all the variety of fishes, even seen within this hobby, making generalities towards the use of salt will get you nowhere. I believe RTR has already pointed out that different fishes have different requirements, and that this goes for dissolved solids and salinity tolerances as well. Hopefully this upplemented that just a bit.

PS - Anyone interested in more specifics regarding the chloride cell changes can take a look at:
Laurent, P., and S. F. Perry. 1991. Environmental effects on fish gill morphology. Physiol Zool 64:4-25.

 

[RTR]

LOL @ YoFishboy! When you keep dozens of tanks (I'm at a low point now and trying to stay there) you need to have labels to keep track of what has been done to which tank and when. For me, 3-5 character designations save space and still provide me the mental image of the tank.

Analyst is where I ended up. Biochemistry and physiology are what I studied, then ran research labs for too long (for DOD, NIH, and the pharmaceutical industry). But it does turn out that data is data is data - if you can analyze any of it, you likely can do the same is several fields. Consulting analysts get paid better than lab heads, and only very rarely work the 60-80 weeks that lab folk live with. That means more time for a life, for fishtanks, for kites, for gardening, and for playing on the web...

 

[cyberbeer65]

The only time I will use salt in any of my tanks is when needed,and take it out through regular water changes.

 

[flyfly]

"Epsom salts. This contains magnesium sulfate which can increase the bowel activity of the fish. But is a good remedy to cure constipation."

Just thought that was interesting.

epsom salts are also great for dosing magnesium sulfate in planted tanks

watchin fish poop is always a plus too