RCS dying

[Cromid]

Hey guys been a minute since I've been on here but just wanted to ask for some advice.
I purchased 10 RCS for my community tank a few months back. They were doing great, or so I thought. Within the past 2 weeks I've noticed a disappearance of most, I e found 3 dead, a 4th literally 5 minutes ago hense this last evening post. Infact I can only see one anywhere and I'm assuming the others have maybe also died.

On the face of it I can't figure out why. My amanos in the same tank are fine.

There is nothing within the tank preying upon them as it's a peaceful community tank with harleyquin rasbora, corydoras and Amano shrimp.
Plenty of plant cover and algae to eat.
Water is generally soft but I will do some tests tomorrow once my replacement test kit arrives.

Anything I could be missing?

 

[AdoraBelle Dearheart]

Have you added anything to the tank recently? Within the last couple of months, maybe some new plants? Where did you source your plants from?

I lost a huge amount of shrimp colony after buying some plants from LFS that turned out to have been imported from Indonesia. Any plants grown outside the UK or EU have to be sprayed with pesticides, and those pesticides interfere with chitin production, leading to shrimp being unable to moult and dying as a result. It took me about three weeks of shrimp dying in ones and twos every couple of days to find out what the problem was, and needed to set up a new clean tank to move the rest of my colony, hoping to save the rest of them.

 

[Colin_T]

do a big water change and gravel clean the substrate.
post pictures
test the water

 

[Cromid]

Have you added anything to the tank recently? Within the last couple of months, maybe some new plants? Where did you source your plants from?

I lost a huge amount of shrimp colony after buying some plants from LFS that turned out to have been imported from Indonesia. Any plants grown outside the UK or EU have to be sprayed with pesticides, and those pesticides interfere with chitin production, leading to shrimp being unable to moult and dying as a result. It took me about three weeks of shrimp dying in ones and twos every couple of days to find out what the problem was, and needed to set up a new clean tank to move the rest of my colony, hoping to save the rest of them.

Ah that's awful! The only thing I've added was some plants cut offs from another tank I have. I don't know if that would have caused it as I have shrimp in that tank that are fine

 

[Ch4rlie]

Am not sure why your shrimps are dying, can you post your exact water parameters please?
That's if you have the test kit of course as you said you getting a replacement kit today according to your first post.

And have you had the amanos for the same period of time as the RCS?

The only thing I can think of is the Harlequin rasboras, especially if they are fully grown, may be stressing the shrimps out and attempting to eat the shrimps as they are opportunist eaters meaning they'll eat anything that comes their way being omnivores. They, the Harlequins, do have very small mouths though but that won't stop them from attempting or trying to hunt the shrimps, amanos are bigger than RCS so teh harlequin leave the amanos alone, perhaps that could explain why the amanos are fine but the RCS being stressed.

Not definitive of course at this point, hence why we ask for the water parameters to possibly rule this out.

 

[Essjay]

I was once told that amanos can also intimidate cherry shrimps. When I was having trouble keeping cherries alive abut 7 years ago I also had amanos and it was suggested that the amanos were the problem - only they weren't in the same tank.

 

[Ch4rlie]

I was once told that amanos can also intimidate cherry shrimps. When I was having trouble keeping cherries alive abut 7 years ago I also had amanos and it was suggested that the amanos were the problem - only they weren't in the same tank.

Interesting, I’ve kept amanos as well with RCS in all manners of different tanks both large and small.

Personally have not seen any issues with the two species together to be perfectly honest.

However, there is one notable difference, in the large tank the RCS bred like anything and had silly numbers of shrimplets in that tank but in my nano tanks, the RCS did not breed so much, in fact not that much at all and in those nano tanks had maybe one or two amanos as well, never thought anything of it at all at the time but now am wondering.

Am not discounting this theory at all since amano ARE much bigger than RCS so I can see why some keepers may come to that conclusion.

 

[hansgruber7]

I would be surprised if it was the Harlequin Rasbora. I kept them with shrimp for a long time and never had the slightest problem. It must be something else.

 

[Cromid]

Thanks for all your inputs guys. I got my replacement test kit so have just performed some tests.

Temp 78/79°
PH 6.7
kH 50ppm-100
gH 50ppm
Ammonia 1ppm
Nitrite 0ppm
Nitrate 5ppm

Anything else I've missed you'd like to know or double check let me know
The ammonia may be explained as I've just found a small hidden area under a piece of driftwood with another dead shrimp in. May be where they go to molt and have done so unsuccessfully.

I've never seen any of the rasbora go for the shrimp, ofcourse it could be happening when I'm not there. Similarly with the amanos, without seeing in action I couldn't possibly say if they are what's causing the issue.

 

[hansgruber7]

Ammonia of 1ppm is really high. That could be the problem.

 

[Cromid]

Ammonia of 1ppm is really high. That could be the problem.

I tested again today and the ammonia is back at 0. Perhaps an issue with the dead shrimp I found