[Cait]

First post, so hopefully I don't screw this up. I have two rock shrimp, that are dull and no longer sitting in the current with their fans open. They have these weird circles on them (see attachment). I'm having one major problem after another with this tank, but I can't seem to figure out this latest one. Any help/advice would be great. Thanks!

 

[Yukiharu]

Ouch. I could be wrong but that looks like pitting to me. What's your gH, kH, and pH?

 

[WaterLife]

Just to know, what other problems have you been having with the tank? They may be helpful in determining what may have lead to this. Used any meds, if so what kind?

I don't know for sure, but I would suspect that your water is too acidic and it is dissolving the shrimp's exoskeleton.

 

[Lyana]

I would agree with water life, that would be my first guess anyway. I had my cherry shrimp in with my crystal reds and their shells started looking kind of pitted. Not as bad as that but close to that. I moved them to their own tank and now the babies are growing up normal. What is your ph, gh etc?

 

[Cait]

I just did a quick strip test,
GH ~ 60 ppm
KH ~ 180 ppm
pH ~ 7.2
Is that the problem??

Bump:

Just to know, what other problems have you been having with the tank? They may be helpful in determining what may have lead to this. Used any meds, if so what kind?

I don't know for sure, but I would suspect that your water is too acidic and it is dissolving the shrimp's exoskeleton.

I have all kinds of algae problems, including blue-green algae. I've put in a new CO2 set up, using poor-mans dosing drops, increased flow, and improved lighting. I put in a new substrate for the plants, and added more plants. I have some algae eaters, and trying to pull out any large bits of algae. I'm treating the blue-green algae with myecin, but so far it doesn't seem to be helping. So my last two options are blackout or the h2o2 method.

Bump:

 

[Yukiharu]

Your gH is slightly over 3 and from what I'm reading the shrimp need a gH of at least 4. I would guess gH issues.

 

[garfieldnfish]

Blue green algae is easily killed off by using Erythromycin (E.M. Tablets). API makes them. You say your are using myecin. I believe that is a spelling error and the mycin you are using should work if it is in fact erythromycin. I only had to use it once many years ago but it took care of the problem within 3 days of treatment if I remember it correctly.

 

[Lyana]

Ph is fine gh is low 5 plus is better, not sure if low gh would cause that though.

 

[WaterLife]

@Cait Very sorry Cait for not coming back to this thread sooner. I had forgotten to check back. From the damage and the behavior that was already present, I doubt the shrimp is still alive now, but hope this info may still help.

I looked up this shrimps water preferences, and the GH, although on the low side, it shouldn't be a big problem. So now I don't think it's damage from too acidic water.

Take a look here
Shrimp Disease? Shell rot? - Care, feeding and breeding - The Shrimp Spot

It does look like it is the disease mentioned.

Seeing as how the disease is a anaerobic gram-negative bacteria and is similar to Vibrio spp., Pseudomonas spp., Aeromonas spp., and Flavobacterium spp., a antibiotic that treats those same bacteria in fish, might work (should, but there's no real mention of a cure for inverts) for the case of your shrimp's bacterial infection.

Antibiotics that typically effective treatments to kill anaerobic gram-negative bacteria are Kanamycin (found in Seachem KanaPlex), Nitrofurazone (API Furan-2), Minocycline (Mardel Maracyn 2 -NOT 1-), Oxytetracycline is not as effective as Minocycline, but is better than Tetracycline, but either could be used, just varying success chances in curing), and Triple Sulfa.

On this study of the disease they mention treatments/cures to stop progression of the disease and I assume upon the next molt the shrimp's exoskeleton should be in good condition.
http://www.nefsc.noa...fs/tmfnec64.pdf
On page 4 (page 10 of 51 for the pdf) is where it talks about possible treatments.

For this type of disease I think Kanamycin (Seachem KanaPlex) usually gives the most successful results. I am not 100% sure, but I do believe Kanamycin is safe for inverts. It's supposed to be safe for use on aquatic plants.
Minocycline (Mardel Maracyn 2, not Maracyn 1 which is Erythromycin and would not be effective) would be my next choice. Pretty sure it is safe for inverts and plants. A lot of meds don't list shrimp/plant safe because they have not tested it on all shrimp/plant species, but from reports by users, many do report it not harming their inverts and plants. I haven't used it myself so I can't comment from first hand experience.
Nitrofurazone is good, but not safe for inverts/shrimp/snails or plants, so that isn't a good to save the shrimp.

So get KanaPlex or Maracyn 2 and dose the tank. Increase water surface agitation and keep the tank clean.