Trouble with brackish environment and red claw crab

[fishbone]

If it's one thing I hate the most, it's feeling helpless. Another thing I can't handle is suffering critters.

Hi guys, new to this forum and hopefully I'll get an answer.
History on the issue.
Set-up a 5 gallon tank for my betta, to which I added 1 tablespoon API aquarium salt. Gravity was at right around 1.003-1.004
Bought a red clawed crab as a scavenger.
Local fish store guy sold it to me as freshwater crab from freshwater tank [also had fiddlers in there]
Found out red clawed crabs fare better in brackish
Googled info and spent an entire week reading and researching. I cannot come across any new articles now
Set-up a brackish environment with a gravity of 1.007
Water temp is right at 78*F constantly, maintained by a 50w Tetra water heater with thermostat
Water is cycled by a Tetra Whisper biofilter
Decor is just rocks and gravel previously used in my 75g tank that housed some coy temporarily, tank which has been dry for a year now. Some plastic plants and that's it
After having the crab with the betta for a week, moved him in his new brackish environment. She was alive and well with the betta. She would spend much of the day inside the filter but the following morning and throughout the day I would find her in various spots in the aquarium. I have seen her eat several times, once shuffling through the tiny rocks on the bottom and another time nibbling at my plant.
Why move her then? Because all the articles online seemed to agree that:
1) in the long term she will be better of in brackish
2) my betta, although very tolerant of her, would eventually end up peing nipped since he would sleep on the bottom

So I moved her in her new environment and trouble ensues
Crab has been in the tank for 3 days now
He barely moves. Doesn't even make an effort to hide anymore. I find him in the morning almost in the same spot as the night before
I have not seen him eat

I grow more desperate by the minute. Help!
I plan on replacing 1 gallon of the brackish with 1 gallon of freshwater to bring the salinity to about 1.005

What else can I do? I'm pretty sure I can vouch for the water quality, I barely dropped 6 little food pellets total. No, I did not cycle it. It is well water, I have used it for the betta as well and not had any problems with it. I used water conditioner for safe measure. I do have a test kit on the way [ordered online, Aquarium Pharmaceutical] but that won't be here for another 4 days AND I made the mistake of ordering one for freshwater. The readings should be pretty close I think.

Any help or ideas are more than welcome. Like I said, I'm feeling pretty desperate. Theoretically it's just a 2 dollar crab but to me it's much more than that. I feel responsible for it's well being as much as I do for my cat, dog and wife. By the way, the wife can't take much of my worring and shuffling

Help me help my critter

[Puffer Pita]

Aquarium salt does not make brackish water. You need marine salt. Aquarium salt does not have the correct trace elements needed for brackish water. All you have is brine.

Also, plopping a creature from freshwater into very salted water will cause osmotic shock, which will damage and can kill them. They have to be slowly and carefully acclimated to the salinity. In addition to that, they MUST have their tank cycled first, as ammonia and nitrites will kill them just as fast as fish, faster even considering they are more deadly in brackish water.

Red claw crabs do indeed need brackish. They tolerate a range of brackish, although as I said, they require marine salt. Yours is a little high though, I keep mine around 1.004. Additionally, the MUST have some way to crawl out of the water. The waterline needs to be low enough and they need to have some sort of structure to get out of the water. They do not like to be submerged all of the time and its not good for their health.

[fishbone]

I forgot to mention.
For my brackish I used Instant Ocean Marine. I only used the aquarium salt for the betta.
The crab also has a decent sized spot on one of the rocks to climb out of the water but he hasn't shown much interest.

So, with all this said and done, what should I be looking at doing?

[Puffer Pita]

Daily large water changes until the tank cycles. Although it may be too late if you didn't acclimate him to the higher SG. How are you measuring the SG?

[fishbone]

I have an Instant Ocean Hydrometer.
This one:
http://www.amazon.com/TK-504-Instant.../dp/B00019JOSO
I'll go home for lunch and suck up 1 gallon out of the 4 and add freshwater. Would that be alright for now? Looking to decrease the SG to around 1.005 or 1.004

[Puffer Pita]

They tend to be hard to clean and use and are fairly inaccurate as a result. I would recommend a hydrometer. They're pretty cheap on Ebay.

[fishbone]

I was told that's one of the good ones and easy to use. It is a hydrometer, am I to search for a different kind?

If it helps, I added almost 2 leveled tbsp per gallon. 4 gallons, 7 tbsps.

[Puffer Pita]

Hydrometers in general are hard to use accurately. Sorry, I mis-typed, I meant you should get a refractometer. Do a search for "salinity refractometers" on Ebay.

[fishbone]

My 7 tbsp should be within the 1.005-1.010 limit, should it not?
I'll do the 1 gallon exchange and hope for the best for now.
I rushed into this because I was basically rushed myself by other fish enthusiasts, being told that no, the crab has to go into brackish pronto.

[Puffer Pita]

No idea, there are too many variables than to say x amount equals y. That's why accurate measurements are needed.

Unfortunately, you were misled. The crab does need brackish, yes, but would have been fine for the short term it would have taken to cycle the tank and acclimate him to the brackish water. However, do not lower the salinity too fast either, or it can also cause osmotic shock. Lower it very slowly.

And just wondering but why do you have your betta in salt? It does not need it and does best in freshwater.

[fishbone]

From what I've read it's actually recommended you add variations between 1 teaspoon to 1 tablespoon of aquarium salt per 5 gallons of water. This will prevent diseases and also help with the general well being.
Info taken from bettatalk.com, amongst others.
If the salinity drops from 1.007 to 1.004 or so, would that still be too much of a sudden change?

Thanks! You have been the most helpful so far. I think osmotic shock is the problem I'm facing.

Refractometers. I don't want to buy cheap inaccurate knock-offs. Is this ok?
http://cgi.ebay.com/Salinity-Salt-Re...QQcmdZViewItem

[Puffer Pita]

Actually it doesn't do either, it neither prevents disease nor helps with general well being. That, unfortunately, is a very common myth that people just parrot but without any basis in scientific fact.
http://www.skepticalaquarist.com/docs/health/salt.shtml


Yes, that would definitely be too big of a change. Change it no more than .001 at the most.

[fishbone]

I tend to trust sites such as bettatalk especially when the owners have bred thousands of offspring and such. I am not dismissing the possibility of the addition of salt to be erroneous, but when faced with conflicting info on the net because there's plenty of it, I go with the folks that have some experience under their belt.
The betta has never been happier by the way. He has a monster appetite too

[Puffer Pita]

Your fish, you're of course free to do whatever you want. Just wanted to let you know that its a myth.

[fishbone]

And I suppose after 3 days of brackishwater, putting the crab back with the betta will also harm him? I'm between the proverbial rock and hardplace, aren't I?

[Puffer Pita]

Yup, pretty much. Just keep him where he is, do daily water changes and lower the salinity slowly.

[Scuba Kid]

Hydrometers read fine, they only give inaccurate readings after being used for a while due to corrosion. Just be sure to rinse it with freshwater after every use and you can get a good long use out of it. That happens to be the same hydrometer i have for my saltwater tanks.

[Puffer Pita]

Agreed, SK, but you have a lot of experience. Its harder for newer people to use them accurately, keep them calibrated, cleaned, etc.

[fishbone]

First off, here is a picture of my set-ups:
Betta [5 and half gallon]
http://img212.imageshack.us/img212/3...quariumgj1.jpg
Brackish [your standard PetCo 10 gallon tank, half-filled]
http://img62.imageshack.us/img62/425...quariumaq6.jpg
Here is a close-up of the rocks and gravel I am using for the brackish.
http://img247.imageshack.us/img247/3...dgravelrf5.jpg
No idea what kind of gravel exactly, I'm told it looks expensive. It came with a 75gallon tank my dad bought from a friend a while back with stand, 4 pumps, rocks. It does have a certain odor to it when moist, almost smells like cement?
So what do you think of them?
These are my very first aquariums ever, so yes, I am a newbie.

Good news, I think. The little one has gone all the way from one corner of the tank to the opposite one, to hide underneath the rocks, in a dark place. When I shone a flashlight briefly it reacted, something that it didn't do up until now. I also stuck my finger close to her and sensed it, which made her move out of the way. Up until now she wouldn't flinch until I actually touched her.

I did a partial water change, I extracted 1 gallon out of the 4 and replaced it with freshwater in an effort to decrease salinity. It went from 1.007 to 1.005 and a half. It's a bit hard to read on my hydrometer but I didn't drop it more than a point and half at most.
I think we're on the right track, hopefully she will eat something tonight [it will be hard to tell] and even surface.

You guys have been most helpful. Not to bash Aquarium Advice [aquariumadvice.com] or anything but my questions have been for the most part ignored

So, she is a female red clawed crab. Once she pulls through this, can I get maybe one more? Can it be a female fiddler crab? If I do, how should I best handle the tranzition from freshwater to brackish?

Now, as far as keeping things clean and taking accurate measurements I would like to say in my defense that I've been building computers as a hobby for 11 years now and I work in IT. I'm pretty good at keeping everything tidy, up to date, organized and can guesstimate a CPU's core temp by touching the heatsink :P

[Puffer Pita]

I don't know about mixing species but I wouldn't get more than 1 more in a 10g tank. They do get territorial and are very vulnerable when they've molted.

The best way to acclimate anything from freshwater to brackish (or SW or vice versa) is by drip acclimation. This explains it pretty well (don't do the float method, that is for adjusting freshwater to freshwater and saltwater to saltwater): http://www.liveaquaria.com/general/g...3319&subref=AI

Guestimating a CPU's core temp is one thing but guestimating water parameters is something completely different. You definitely need a test kit. I highly recommend Aquarium Pharmaceuticals Freshwater Master Test Kit. It has all of the basics and will last a good long time.

Keep up with the daily water changes, even if you have the salinity where you want it, until the cycle completes. You'll need the test kit to know for sure when that is - when the ammonia and nitrites read zero and there are some nitrates. Then you can back off to doing water changes and gravel cleaning once a week. Don't clean the gravel during the cycling process though.

Not sure what water conditioner you are using but I highly recommend Prime, especially during a cycle. It will detoxify the ammonia and nitrites, making them less poisonous to the livestock but will leave them available for the cycle. Its also safe in overdose amounts.