Aquarium Salt Dosing

[DiscusKeeper403]

I picked up a package of doc wells aquarium salt for freshwater fish. I heard bettas like it so i'll give some to them, what about my 25gal high tank? it has 2 angels and some corycats, will the corycats hate it?

Thanks,

DL

 

[vic]

Salt is not a good idea in any freshwater tank. Freshwater fish like fresh water, not brackish or salt water.

 

[vancouver]

I know cories don't like salt. I've heard it burns their skin.

I believe in bettas salt is used to give their immune system a boost.. or something like that.. I only use salt with my bettas if they don't look well.

Not something to just throw in the tank for no reason, but it can be useful.

 

[Imber]

I've used salt in my betta tanks during quarantines or to help with fin rot or ich. Usually 1 tsp per gallon will do the trick for fin rot.

I've heard mixed reactions on salt with corys, but the general consensus is it's not a good idea to use it with them so I've not been brave enough to try it.

Oh and another tip that I can give you is that you don't really need to spend all that money on aquarium salt. Any pure salt will do. You just have to be sure that it doesn't have any additives like anti-caking agents. Personally I use kosher salt because it's cheap and it dissolves better than aquarium salt.

 

[Bignose]

This is from a thread a few months back: ( http/www.fishforums.net/index.php?showtopic=155280 )


Regarding what fish can and cannot handle salt. This is from a very knowledgable member on another fish forum:

Primary freshwater fishes are those that have remained, as far as we can tell from the fossil record, in fresh waters throughout their evolutionary heritage. Fishes that fall into this category include Characins, Carps and Catfishes.

Secondary freshwater fishes are those that had marine ancestors at some point in past time, but which moved into freshwater in order to occupy various niches. Cichlids are an example of secondary freshwater fishes - their nearest relatives are the marine Damselfishes of the Family Pomacentridae, and it's highly likely that both Families shared a common (and marine) ancestor.

Consequently, the secondary freshwater fishes still have at least some degree of osmoregulatory capacity for dealing with salt in the water, while the primary freshwater fishes never evolved it in the first place. So, placing primary freshwater fishes into water containing salt is a bad idea, and even modest amounts will kill them. Secondary freshwater fishes, on the other hand, can tolerate small amounts of salt, and indeed some members of secondarily freshwater Families are brackish in nature - the Cichlid fish Etroplus suratensis springs to mind as one example. Cyprinodontiformes also fall into this category - both the egg-laying Cyprinodontidae and the live-bearing Poeciliidae are also secondarily freshwater, some of the latter Family being fully brackish in the wild (indeed, the Giant Sailfin Molly, Poecilia vivipara, is fully euryhaline, and can live in fully marine water, as specimens captured in seawater off the Yucatan Peninsula in Mexico testify eloqwuently).

Quite simply put, if your aquarium contains any primary freshwater fishes, do NOT add salt, as those fishes will suffer considerable stress if exposed to salt, and may even die. Even in the case of secondarily freshwater fishes, salt is only a good idea if the fishes concerned are KNOWN to inhabit brackish waters in the wild.

Most fishes fall into the category of being stenohaline, namely, they are either freshwater or fully marine. These fishes should only be exposed to the kind of water in which they occur in the wild with respect to salt content. Euryhaline fishes, that can migrate with some degree of freedom between freshwater, brackish and fully marine environments, are much fewer in number, and tend to be conspicuous in this regard when encountered in the textbooks - fishes such as Scats, Monos, Therapon jarbua, velifera Mollies and one or two of the Puffer Fishes are notable for this. Within the euryhaline division, there are those that can migrate more or less at will, and those that do so developmentally - the Puffer Fish Tetraodon nigroviridis is developmentally euryhaline, spending its juvenile stages in freshwater before migrating at a steady pace to increasingly saline waters until, as adults, they are strongly brackish or fully marine fishes. Once again, and I cannot stress this enough, it pays to do the research and find out what your fish is!

Cory catfish developed in a salt free environment. Their bodies do not have the mechanisms to deal with salt in the water. It has virtually nothing to do with scales or scaleless, it has almost everything to do with osmoregulatory processes which the cory catfish simply does not have to deal with salt.

I've also got some comments in this older thread ( http/www.fishforums.net/index.php?showtopic=157186 )

 

[nmonks]

Hello bignose --

While, broadly speaking, I wouldn't disagree with much of that quote you've posted, as is typical in biology it is dangerous to take a general observation and apply it as a universal law. Biology isn't physics.

Primary freshwater fish families, it is true, generally have a lower tolerance for salt than secondary freshwater fish families, but, and this is important, the "rule" applies to families, not species. The Cichlidae are a primary freshwater fish family, but an angelfish isn't a primary freshwater fish. Within each family there is plenty of variation.

For example: if you were to go fishing in the tidal Thames near Putney, you'd get not just marine fish like sprats and flounders but also plenty of specimens from primary freshwater fish families, specifically roach and dace.

This would be replicated in any other body of brackish water you'd care to name. In North America you'd find ictalurid catfish, for example, and in India bagrid catfish. There are even tetras that inhabit slightly brackish water, as well as species of loach, plec, carp, labyrinth fish, and spiny eel -- all members of primary freshwater fish groups. Admittedly, most of these have a fairly low tolerance of salt, and won't go beyond about 25% seawater, but there are plenty of exceptions. Mystus gulio, for example, can live in seawater.

Put it another way: there isn't a sudden die-off of fish from primary freshwater fish families at the first whiff of salt. All fish have some tolerance of salt (bony fish evolved in brackish, not fresh, water) but it may only be a trivially low tolerance. But this has less to do with which group (family, primary or secondary) they belong to and far more to do with their all round tolerance and adaptation to specific water conditions. Goldfish and channel catfish, for example, tolerate a broad range of water conditions, including pH, hardness, temperature, and salinity. Discus and mbuna on the other hand, are adapted to very specific sets of water conditions and have little to no tolerance of brackish water. Goldfish and channel cats are, of course, from primary freshwater fish families, and yet are more tolerant of salt than the discus and mbuna from secondary freshwater fish families.

So while I agree with your advice that adding salt to a tank with Corydoras and angelfish is pointless and possibly harmful, this isn't because the catfish are from a primary freshwater fish family, but because both these fish have evolved to live in soft, acidic water. You can find fish in both their families that tolerate brackish water well. Hoplosternum (in the same family as the Corydoras) lives in brackish water marshes in its natural range and apparently tolerates up to 16 ppt* (that's about 50% seawater!) and in fact grows more slowly in freshwater than slightly brackish**! Likewise, within the cichlid family there are plenty of species tolerant of brackish water, and a few that will even live and breed in seawater.

Incidentally, David Sands, a pretty well known catfish expert, considers low doses of salt to be harmless to Corydoras and says that because of this they can be mixed safely with things like mollies. While it isn't clear in his book exactly what he means by a low dose, I'd have to assume something like 5-10% seawater.

Cheers,

Neale

Quite simply put, if your aquarium contains any primary freshwater fishes, do NOT add salt, as those fishes will suffer considerable stress if exposed to salt, and may even die. Even in the case of secondarily freshwater fishes, salt is only a good idea if the fishes concerned are KNOWN to inhabit brackish waters in the wild.

*Nico, L. G., S. J. Walsh, and R. H. Robins. 1996. An introduced population of the South American callichthyid catfish Hoplosternum littorale in the Indian River Lagoon system, Florida. Florida Scientist 59(3):189-200.
**Mol, J.H. 1994. Effects of salinity on distribution, growth and survival of three neotropical armoured catfishes (Siluriformes, Callichthyidae). Journal of Fish Biology 45:763:776.

 

[Bignose]

Neale,

we've been over this before, like in the previous threads I linked to that I hope the OP will read through. We basically said the same things, that there are generalities and specifics. Remember I found papers that back up just how low of a tolerance some species of Corydoras has, and some species of Corydoras are relatively hardy. I really am talking in generalities, and completely acknowledge that there are exceptions. But, on the whole, you have to agree that primary and secondary fishes react differently to salt.

My sincerest hope is that anyone who even considers adding salt to their tanks will research their specific species they own and really think this issue through. My goal is more to spur people into researching this issue on their own, rather than arguing specifics, especially on a species by species level. Especially since the conclusion we came to last time is that both Neale and I are really are saying very closely the same exact thing.

 

[DiscusKeeper403]

Thanks guys! I skimmed through but i'm really tired so i'll read thoughly in the morning!

 

[Tommy Gunnz]

First, let me say that I am not trying to argue or spur on a huge debate with my comments here so take it easy on me...and DiscusLova as well.

First, this whole thread sounds as if we are talking about a huge amount of salt being added to this freshwater tank, which is not the case here or at least should not be the case. The correct amount of aquarium salt that should be used in this situation, if any at all, would be 1 tablespoon per every 10 gallons. This is because of the corys, otherwise it would be safe to put in 1 tablespoon per every 5 gallons so long as there are not scaleless fish in the tank.

Secondly, we are talking about two TOTALLY different types of salt here and that has to be made clear. I have this same salt sitting right next to me and it is NOT sea salt, ocean salt, or reef crystals and is NOT intended to be used to create brackish or saltwater. It is just plain old salt with no Iodine in it or other trace elements. If one was to use this salt to fill up a saltwater tank, nothing would thrive since alot of things would be missing from the water. The same can be said about brackish water since that salt should be of the same variety as saltwater tank salt. Please keep these differences in mind before saying that ANY salt should not be used in ANY freshwater tank.

The salinity of a brackish tank is supposed to be around 1.015, if I recall, and it is not just the ordinary salt that the aquarium salt in question is. There is so much more trace elements and needed components in brackish and saltwater salt and these are the things that help keep fish and inverts healthy.

This salt that DiscusLova is talking about has some good properties such as helping fish grow a suitable slime coat. It is also an AWESOME salt to use for treating Ich with the more natural "salt and heat" method. True, it is not always good for scaleless fish but it can still be used in smaller amounts like I said before.

In reality, there are MANY of us who keep brackish water fish in freshwater for their entire lives and I for one, do not know why that is. For example, Mollies are absolutely brackish water fish and they can also survive for a long time in saltwater tanks. Puffers like the figure 8 puffer I believe, are brackish water fish once they hit adulthood, but I have yet to hear anyone who has planned to change his or her tank over when his or her puffer needs it. And while I am not experienced with Angels, many, if not most of them are truly brackish water fish and no one pays attention to that hardly.

So, my point here is that you all are being too rough on DiscusLova and I havent seen any true reason for this if it is understood about the differences between the two salts and how much will be put in the tank. I really feel bad that this has gotten so misconstrued and I think another look should be taken into DiscusLova's question so that a good answer can be given rather than assuming that if he puts some salt in, he needs to go get some clownfish for the tank.

Again, not trying to start a problem here, just wanted to help clarify things and see what else can come out of this question.

 

[nmonks]

Hello Tommy,

Let's take this step by step.

First, this whole thread sounds as if we are talking about a huge amount of salt being added to this freshwater tank, which is not the case here or at least should not be the case. The correct amount of aquarium salt that should be used in this situation, if any at all, would be 1 tablespoon per every 10 gallons. This is because of the corys, otherwise it would be safe to put in 1 tablespoon per every 5 gallons so long as there are not scaleless fish in the tank.

Dismiss any recipe that involves adding salt by volume (i.e., spoonfuls). Once a box of salt is opened, the salt absorbs water from the air. So over time, any given spoonful will contain less salt and more water than before. Hence, the only accurate way to use salt is by adding it to water and measuring the specific gravity. Any source of information that doesn't comment on this is suspect. Secondly, whether or not a fish has scales has NOTHING whatsoever to do with its tolerance of salt. Discus have scales, but minimal tolerance of salt. Moray eels have no scales, but live in the sea. So please, remove that nugget of information from your brain -- it's worthless.

Secondly, we are talking about two TOTALLY different types of salt here and that has to be made clear.

No, we're really not talking about different things. Aquarium tonic salt is more or less pure sodium chloride. Sea salt (marine mix for the aquarium) is about 80% sodium chloride. In terms of osmotic effect on fish (which is the issue, not the minerals themselves) both are identical for all practical purposes. Over the long term, yes, marine salt mix is what you need for marine fish or brackish water fish, but over the short term there is no difference is the way a given salinity using either will draw water out of any fish living in it.

The salinity of a brackish tank is supposed to be around 1.015, if I recall...

The specific gravity of a brackish water tank is typically 1.003 at the low end up to 1.010 or so at the high end. Marine aquarium fish can be kept at 1.018 upwards, and marine invertebrates around 1.024.

This salt that DiscusLova is talking about has some good properties such as helping fish grow a suitable slime coat. It is also an AWESOME salt to use for treating Ich with the more natural "salt and heat" method.

There are two issues here. Fish produce extra-thick slime coats when their skins are irritated. If you want a human analogy, it's getting a callous on our feet when we walk barefoot a lot or in poorly-fitting shoes. Our skin responds to the stress by developing a coat of dead skin cells that protect the living tissues within. Likewise, where fish are irritated, their produce extra mucous on the skin to protect themselves. A fish should have a perfectly adequate slime layer under its optimal conditions (which, for angelfish and discus, would be very soft water at about pH 6). Secondly, I do not dispute that salt is useful for treatment. But there's a difference between using salt as a short-term tonic in the aquarium and using salt all the time. I don't know any professional aquarists who recommend the latter. Rather, experienced aquarists put the accent on water quality and trying to match the water chemistry of the fish's natural habitat. There are exceptional situations where adding salt can help. If you have soft and acidic water, then adding salt to it will make life better for guppies, swordtails, and so on even though those fish don't actually need the salt per se. It just helps them deal with soft and acid water, something they do not experience in the wild.

In reality, there are MANY of us who keep brackish water fish in freshwater for their entire lives and I for one, do not know why that is. For example, Mollies are absolutely brackish water fish and they can also survive for a long time in saltwater tanks. Puffers like the figure 8 puffer I believe, are brackish water fish once they hit adulthood, but I have yet to hear anyone who has planned to change his or her tank over when his or her puffer needs it. And while I am not experienced with Angels, many, if not most of them are truly brackish water fish and no one pays attention to that hardly.

Oh boy! Yes, some brackish water fish will survive in freshwater for months, years, even indefinitely. This is more about their hardiness than the cleverness of the aquarist. In all cases, brackish water fish do better in brackish water. Mollies do not get fin-rot or fungus, for example. Figure-8 puffers live much longer in brackish water than fresh, and green spotted puffers something like twice as long in brackish water. So anyone keeping a green spotted puffer or figure-8 puffer in freshwater is basically condemning their fish to a shorter lifespan. Scats and monos kept in freshwater tend to be off-colour and nervous, and scats in particular are prone to lymphocystis when kept in freshwater. I have no idea who told you angelfish are brackish water fish. They come from the Rio Negro, hundreds of miles inland, where the water is basically zero hardness and a pH of 6 or less. Please, on brackish water stuff, trust me. I'm literally the guy who wrote the book on the subject.

So, my point here is that you all are being too rough on DiscusLova and I havent seen any true reason for this if it is understood about the differences between the two salts and how much will be put in the tank. I really feel bad that this has gotten so misconstrued and I think another look should be taken into DiscusLova's question so that a good answer can be given rather than assuming that if he puts some salt in, he needs to go get some clownfish for the tank.

Seriously, all I'm trying to do is save you some money and make your fish healthier. There is no evidence at all that adding salt to aquaria containing freshwater fish is better than keeping those fish in optimal water conditions depending on their origin. In fact, as sure as God made little green apples, I can tell you that keeping discus in soft/acid is better than tap water with a bit of salt, and this is equally true for stuff like Tanganyikan and Malawi cichlids, which need hard water with very different minerals to seawater.

Aquarium "tonic" salt exists only for one reason: to extract money from aquarists who don't know any better. It is right up there with carbon as something most aquarists do not need. That people defend the stuff I find bizarre, because aquarium salt is nothing more than a con, pure and simple. Decades ago it existsed because filtration was less good and adding a bit of salt moderated the toxicity of nitrite and nitrate. By adding salt you covered up the problems with filters and also didn't need to do so many water changes. But that was then, and this is now. We know understand that new aquarium water is better than old aquarium water (something people vigorously denied during the 60s and 70s). Filters, even the cheap ones, are very well made and designed, and there's really no reason to have any nitrite in your aquarium. In short, you don't need tonic salt.

The only time you might need it is for doing saltwater dips or as part of a treatment in the tank, but in those cases, either non-iodinised cooking salt or proper marine salt mix will work just as well. The former type of salt is cheaper and you probably already have some, and the latter stuff you'll definitely have if you're keeping marines or brackish. Tonic salt is just overpriced cooking salt and that anyone still buys the stuffs is surreal.

Sincerely,

Neale

 

[Bignose]

And while I am not experienced with Angels, many, if not most of them are truly brackish water fish and no one pays attention to that hardly.

I just wanted to reinforce nmonk's post on here that freshwater angelfish are in no way whatsoever a brackish water fish. Please research their native habitats before posting information like this. You will find, just as nmonks said, it is very soft, very acidic water with virtually no mineral content whatsoever. Now, commercial breeders have been able to take these fish out of their natural waters -- the fish is now generally hardy enough to survuve and live a long life in almost any tap water. They are not nearly as particular about their water as the average discus is, for example. But, angels (or pretty much any fish, for that matter!) will still be at their best if you can replicate their natural waters, which in this case is almost completely mineral-free water.

 

[Tommy Gunnz]

OK, so I admit that I was wrong with the angels being brackish and was thinking more so about the Mono. I appologize and shouldnt have made that comment based upon my fading memory.

Again, I am not trying to start a huge problem here and I am learning from this thread as well. I appreciate the information and so there is a lot of good coming out of everyone's comments.

Still, I think that there are differences between the two salts and I wanted to make that point more so that people do not take the advice of the LFS that my brother recently bought a spotted puffer from, along with about 20 little pint sized milk containers of aquarium salts. This is not the right salt to be used to create a brackish environment...correct?

I also agree 100% that many fish can be kept in the wrong type of environment (whether that is too salty, not enough salt, wrong Ph, too small of a tank, too large of a tank, etc....) and apparent success can be gained by doing so, however like you said, the fish are not going to live as long or grow to their full size or coloration. This is why I am usually an advocate for pointing things out like this.

Also, in a very popular aquarium magazine that I got last month, there is an article along the same lines as this thread only dealing with keeping columbian black-finned sharks in freshwater. The reader asking the question was using 'aquarium salt' and the reply stated that a "parasitologist and distinguished aquarist" pointed out that Sea Salts/Ocean Salts are known as CATION salts (emphasizing, not yelling) and brackish fish should be kept in salt water with cation salts, not 'tonic' salts as you point out aquarium salts are.

I guess that you could also be very correct about the aquarium salts being used solely to make money but I still dont know why some very large influences in this hobby would support their use. I have seen, on a very popular online store (at least popular in the United States) an article stating that Ich can be treated with aquarium salts and higher water temperatures which, logically thinking would reduce the potential income from sales of Ich medications and reduce their income to $2.00 boxes of salt.

So, I am completely open to hearing a different point of view on this and if you can show me why some of this sort of information and ideas are being thrown around so commonly in this hobby, I would certainly change my mind as well as methods of dealing with my tanks. I have both freshwater and a larger saltwater tank that all have seemingly thrived so far and so if I can increase my success with these tanks, then I am all ears.

 

[nmonks]

Tommy Gunnz --

No worries about the angels. I'm certainly not here for a fight. I just like to do my bit to help clear up misunderstandings.

Back when I started keeping fish, monos were usually called "Malayan angels". They don't seem to have been called that for years. Odd.

Anyway, if you had a green spotted puffer and added some "tonic" salt instead of true marine mix, it wouldn't harm the pufferfish, at least not in the short term. But yes, you're right, that was bad advice from your LFS. What you want is proper marine salt mix. Set the specific gravity of the tank to 1.005 if the puffer is very small, and 1.010 or more if it is more than about 8 cm/3 inches long. In other words, one box will make about 5 times the amount of brackish water than seawater for a small pufferfish, and about 3 times as much for strongly brackish water for an older pufferfish.

"Cations" and "anions" are positively and negatively charged ions respectively. So sodium ion (Na+) is a cation, and chloride (Cl-) is an anion. Both tonic salt and marine mix have a mixture of both, so I have no idea what the author of that article was getting at. The chemical difference between tonic salt and marine mix is this: tonic salt is basically NaCl (i.e., table salt) while marine mix is mostly NaCl but also about 1/4th stuff like various sulphate ions, calcium carbonate, and so on. The carbonate is especially important because it buffers the water and raises the pH. Tonic salt alone doesn't buffer the water at all. The main reason brackish (and marine) fish like sea salt rather than tonic salt is because without the carbonate salts the pH and hardness are too low. Brackish water fish want a pH about 7.5-8, and marine fish 8-8.2 or so. The buffering quality -- the resistance to pH change -- produced by the carbonate is also critical, as marine fish especially do not tolerate sudden changes in pH. Since you keep marine fish, you probably already know this!

The tonic salt thing is basically a con. I wish shops wouldn't sell it. If you need to dose your aquarium to fight whitespot, then go use table salt (without iodine, of course) and save a few bucks. If you have brackish water fish, then get real marine sea salt mix and add not just the salinity they need but also the pH and hardness.

Tonic salt has just been around so long (like carbon for filters) that people believe that because it is on sale, it has to be useful. Neither carbon nor tonic salt are particularly useful except in very specific circumstances, and even then, there are probably better alternatives.

Cheers,

Neale

 

[fishdawg]

ill summ this up. dont use it!

 

[vancouver]

Only use it on your bettas if they aren't looking well.