# RCS die off



## coco_moo (Jun 27, 2010)

I have a five gallon cherry shrimp tank, which has run with no problems for about the last 2 years. However, I've noticed that in the past 4-6 months there has been a big drop in the population. The tank has a sand bottom, and is usually home to a few different plants at any given time. The plants usually migrate into the tank when they get algae problems (we have loaches in all of out other tanks, so inverts aren't really an option). We don't dose ferts in any of the tanks, so copper shouldn't be a problem. We also bought about 25 more (cherry) shrimp in a fish auction this fall and still the population is dropping. I'd hate to guess how many shrimp are in the tank now. Twenty max.

Any ideas as to what the problem could be? We've seen berried females within the past couple of weeks so I really don't know what could be going on.


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## Gordonrichards (Apr 28, 2009)

Photo of your tank please.
Parameters such as ph, heat, light.
Water changes?


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## coco_moo (Jun 27, 2010)

Light is 2 WPG, heat is kept between 74-76 and pH was 6.5.

The tank is an open top and about a fifth of the water evaporates a week so we refill as needed and do 30% water changes around every two weeks. Maybe more often would help? :1

Our camera is on the fritz, but the layout of the tank is sand, a nano power filter (with a sponge on the intake) and a sponge filter (and a heater). Visiting plants are in plastics boxes filled with eco-complete and the tank has two permanent residents (crypts ) and some java moss. 

The plants in with the shrimp now are the crypts, rotala wallichii, didiplis diandra, some giant red rotala and a small madagascar lace leaf, all of which will be moved out in a few weeks. So there is definately no shortage of flora. 

I'm wondering about the hardness. Last time I checked it was fairly low, despite the fact that we have a few shells in there to keep it up. Any other ideas on how the hardness could be brought up?

The tank has a snail problem (and the assassin snails don't seem to be helping), I don't suppose that could affect anything...


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## trag (Jan 9, 2008)

coco_moo said:


> I have a five gallon cherry shrimp tank, which has run with no problems for about the last 2 years. However, I've noticed that in the past 4-6 months there has been a big drop in the population. :


Check your nitrates. I had a good RCS population in my 30 gallon guppy tank, but the guppies bred until there were so many that even with 70% water changes every two weeks, the NO3 was hitting 70ppm. And all the shrimp vanished. I had enough filtration to handle the NH3 and NO2, the problem was that even with heavy plants, the NO3 accumulated too fast.

My 5 gallon tank full of RCS during the same time period was just fine and still is.


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## vicky (Feb 18, 2010)

I have to wonder what is causing the snail problem. Whatever is is could be an issue. Also, the snails use calcium to make their shells, making your water even softer. You can crush the snails in the tank, turning them into food, but too many at once may foul the water. If you remove them, you are removing the calcium they contain. I add crushed coral or oyster shell to my tanks as I have soft tap water. I also add a cuttle bone (like you put in a parakeet cage) to the water in my shrimp tanks. It sinks, but it takes a few weeks. The snails in those tanks are noticeably more difficult to crush. Hydra and planaria are two pests you may have picked up that can kill your shrimp. The wormer Fenbendazole is said to safely kill them, but do your own search. As mentioned nitrates can also be a problem. Floating plants are an easy, cheap and fast way to remove excess nutrients. 

I hope these ideas are helpful to you, that you are able to figure out what the problem is, and find a speedy solution. Keep posting.


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