Brackishwater and goldfish

[Fantail_Lover]

Are goldfish adaptable to Brackish water? I don't normally put any salt in my freshwater aquarium at all, but I have a Fiddler Crab on its way and its highly recommended to add a small amount of salt to the water, just so the crab has an easier time breaking out of its shell when it needs to go through the molting process. I read an article online that says that fish usually need a little salt in the water just for general health. Also fish have kidneys that can adjust to a salt change in the water. I just don't want to hurt my goldfish, especially before their new friend gets here - but then again I want the crab to enjoy its new habitat. Anyone have any advice?

 

[Zman16]

I don't think goldfish can, but I'm more of a tropical fish person.

 

[Brack-Man]

The kind of salt used for general fish health is different than what you would use to make your tank brackish... aquarium salt for health marine salt for brackish... I dont dont know about goldfish in brackish water though, but I would have to say probably not... Have you thought about getting a seperate set up for the crab? Might be your best choice.

 

[Fantail_Lover]

I am quite confused on the whole matter at this point. The article I read says that small doses of Aquarium salt (1 table spoon to every 5 gallons of water) should be safe for all BRACKISH fish. Although, they do not include goldfish on their list of brackish fish, I know alot of people who say that adding this aquarium salt can be very beneficial to all types of fish and reduce any stress the fish may be having. I asked at the LFS and they said the same thing, and he said it shouldn't harm my goldfish one bit. I think alot of people may get aquarium salt and marine salt confused.

Either way, I'm going to add some AQ Salt to my tank tonight and see how the fish are doing in the morning. I'll update on the matter tomorrow when my crab arrives. P.S. - anyone know of a cheaper way to get crabs from online other than Aquariumfish.net?? They charged me $25.00 S/H on my $3.00 crab - *thumbsdow

 

[Brack-Man]

Aquarium salt is not what is used for making brackish water... it will however be fine for goldfish... but it in no way benefits brackish fish, it does not have the the trace minerals needed for their well being... Marine salt, what is used for salt water tanks, reef tanks is what is what is required to achieve the proper salinity for brackish water tanks does... I believe what the lfs guy is trying sell you and tell that is ok for brackish water is Aquarium Pharmacuticals Aquarium Salt, yes?... what you need is Instant Ocean or some other type of marine salt mix, which will not be ok for the goldfish.. I hope this makes things a little more clear for you if not maybe some one else will chime in soon that can explpain it a little better , but thats as plain as I can make it. Good Luck

 

[Fantail_Lover]

Well I dont know what to think about the crab now. I hope the little bit of salt that I added to my tank will help him Molt but I kinda doubt it now. I read closer on the label of my AQ salt and it actually says its ok for Goldfish. Says for every 1 gallon add 1/2 tsp of salt (which actually seems like alot) so I added like 1/2 tsp for 12 gallons, lol. I noticed an immediate difference in the fishes behavior, sorta frantic, so I doubt thats good. But they look O.K. now so I dont think it hurt them any.

 

[Seleya]

I don't usually recommend crabs with goldies, especially in such a small tank. You'd be better off getting a larger tank for the goldies and setting up the 12 for the crab. Many crabs need to crawl out of the water occasionally (onto a branch works well but you need lower water levels to achieve that) and would benefit from some marine salt with all the trace minerals. I am not sure where fiddlers fall into it, you'd have to ask in the appropriate forum. Goldfish can handle aquarium salt (not marine salt) and some goldie keepers use it regularly. I only use aq. salt when they're sick, new or if any ich occurs in any of my tanks. Goldfish tend to sleep on the bottom, where the crabs are....

 

[homebunnyj]

If you don't give the crab a brackish environment, his lifespan will be very short. If you put the goldfish in brackish water, being a freshwater species, his lifespan will most likely be considerably shortened.
As brack-man explained, putting in aquarium salt does not make brackish water, no matter what the ill-informed writer of that article said.
Brackish is between the fresh water of a river and the marine water of the open sea. Crabs live on beaches and in salt marshes (mud flats), so you can see that their water would be a mixture of marine and fresh. Instant Ocean marine salt has more minerals in it than just salt. If you use aquarium salt, your crab will be missing out on many important elements in his environment.
Your crab also needs a land area. You would probably need to lower the water level in your tank to accomodate this. That would effectively decrease the volume of water for your goldies. One goldie needs ten to twenty gallons of water to live in. If you have two in somewhat less than twelve (after adapting the tank for the crab), you will have even more water quality issues than you have now.
Putting them together in any environment is not fair to either one.
Hopefully, you can get a bigger tank for your goldies, or rehome them and get a fish which really does like brackish conditions, like a molly, maybe, for your 12g. (Anyone... correct me if I'm wrong, please?)

 

[Limi310]

HomebunnyJ is absolutely correct about the Fiddler. Generally, they can live 2-4 months in FW and then they will die. I know this from personal experience. Unfortunatly, they are almost always sold as a fresh-water crab.
Like others have said, is it possible for you to set up an environment just for it?

 

[Big Vine]

I agree with Limi, homebunnyj, and Seleya.

I'd just like to add that, in my research on these little critters, I also learned that it is best to keep a dish of (dechlorinated) freshwater in with them, so that they can go and bathe in it whenever they feel the need to "re-equilibrate" their salt levels, or something like that.

Forgive me for not knowing the appropriate terminology, but to me this theory makes sense.
Obviously this would require having a lower water level, along with a sloped sand/gravel area of some sort that allows the crabs to get out of the brackish water and onto land. I've heard that sand is better, since they do like to burrow a fair bit.

Big Vine

 

[MOsborne05]

I bet you got that information from www.aquariumfish.net who wants you to buy from them. And the lfs said that aquarium salt was fine, because he wanted you to buy aquarium salt from him. Like everyone else already pointed out, you need two seperate tanks. Or else your buying a $30 crab that will only live for a few months

BTW, I didn't have a very good experience with them, so hopefully your experience is better than mine.

 

[Fantail_Lover]

Thanks for all the advice!
Let me start off by saying that 1 goldfish does not need 10 to 20 gallons of water to live in. This is way off, I don't know where you got that number. They do produce more waste then other fish but if you keep the temperatures down below 80 degrees F they produce less. I've kept these same 2 goldfish in the 12 gallon for quite some time now and they love it. Also my aquarium is very stable, the numbers in my signature haven't changed for months.

Now for the crab: I know that these crabs usually need brackish water, but the guys over at aquariumfish.net insure that they keep theirs in large tanks with freshwater and that they live for a long time. To accomidate the crabs need for occasional dry land I have incorperated a medium sized glass jar with a small opening on one end. Air has been trapped inside of the jar and a large rock positioned so that the crab can easily have access to the surface.

I just got my crab in the mail today and although I know its too early to tell, I think he likes his new environment. I've added some of that Aq Salt to the tank (for what its worth) and the crab just found the jar I have set up for him. He is currently pirched in the air pocket cleaning him self. I'll watch his progress closely and update if anything happens.

 

[Seleya]

I would HOPE you'd keep a goldfish tank below 80, heck, I'd hope you'd keep it quite a bit below 80. You obviously feel 4 months is sufficient time to know everything about goldies but it's a pretty established rule amongst experienced goldie keepers that it's 10 gallons minimum for each fish with a 20 gallon tank being the absolute minimum for a single goldfish. I prefer to err on the side of understocking to ensure my fish get the full benefits of good water quality in addition to a serious maintenence schedule. Otherwise, I could just cram them where they fit and hope they survive rather than do what I do to help them thrive. If your two goldies reach full size, they won't be able to turn around in that tank.

If you wish to listen to the people profiting from your purchase, that's your decision -- we see people regret that decision on this forum on almost a daily basis. With all this advice pointing in one direction, it's hard to give up what one wants but sometimes it's for the best interests of the creatures if one does. I would advise you check your parameters with a different test kit if NONE of your parameters have changed at all. Nitrates at the very least should shift around even a little.

 

[MOsborne05]

Good luck with that $30 crab

And goldfish do need at least 20 gallons each because if they don't have enough room then their bodies stop growing but their organs continue to grow. Eventually your little goldfishes will explode because they don't have enough room. Trust me, I saw it happen when I was in class where the teacher kept 6 goldies in a 20 gallon tank. It's not a pretty sight and it is one heck of a mess. And then your parameters will drastically change and probably kill your crab.

 

[Fantail_Lover]

I've never heard of goldfish exploding from the inside. What about people that keep goldfish in little bowls for years and years? My friends goldie just died after 14 years of living in a bowl. As for "knowing everything" about goldies, I never said that, but I just believe that the 20 gallons per statement is drastically incorrect. Yes its true that those parameters never change, as for the nitrates they bounce around a little due to the + or - amount of plants I add to the tank. Other than that my tank is very stable. I am considering setting up my other little 2.5 gallon with a low level of brackish water. That way I can keep my crab a little happier, but until then we'll see how things go.

 

[Seleya]

Dumb luck with a notably hardy fish can hardly compare to good fishkeeping. Comets can easily reach a foot, ryukins easily 7 - 8". I have ~10 yr old comets, who live in my garden pond in warmer weather, I cannot imagine putting in a bowl or 10 - 12 gallon tank -- they wouldn't be able to turn around due to their size! I also have 7" ranchu and orandas I cannot imagine doing any more than existing, nor would my even larger butterfly moor done more than spent her life just hovering and turning around in a tank of that size. If someone keeps a fish in far less than optimal conditions and they survive, that's the exception, not the rule (and, in some cases, in reality, a succession of victims replaced when the kids weren't looking!) -- I can't imagine they thrived or reached their full potential.