The other shrimp from my most recent Bob’s Tropical Plants order was five blue berry shrimp, neocaridina palmata. I chose these on a whim in part due to low price compared with other varieties, and also to have shrimp that would let the plants remain the focal point by blending in more easily than some of the brighter color variations available.

I had noted in a few earlier blog posts that I was having trouble keeping these blueberries healthy. Despite being in a larger tank with more plants and a higher flow filter than the Orange Sunkist shrimp tank, my blueberries were dying while my orange were thriving. I began performing daily small water changes and vacuum sessions, after which the blueberry shrimp would always perk up. Yet by that night or next day, they were often back to being sluggish. The plants were also struggling to grow as quickly as others of their species in similar tank setups. I documented some of the efforts I took to increase water flow and filtration in this tank in a previous post.

While the tank did experience a burst of new growth from the increase water flow and continued water changes, every morning I would wake to find my shrimp still being sluggish. Healthy shrimp are constantly filtering the water, with their limbs a blur of movement. These blueberries would be still, often staying in one location for long periods of time. Even when grazing, their movements were slow and labored. After a morning mini water change, normal behavior would resume. There must have been something else in the tank affecting my blueberry shrimp negatively.

Just to really confirm my new theory, that something in the tank was leeching harmful substances into the water – I decided to add in a currently healthy and thriving shrimp from a nearby tank. My newish red cherry shrimp colony was doing great, so I snagged an active, healthy looking red cherry to be moved to the blueberry shrimp tank. If a newly added, healthy shrimp began exhibiting the same symptoms as the unhealthy shrimp, then the tank environment itself is most likely the cause of those symptoms. At this point, I was much less worried about cross breeding than I was about my blueberry shrimp, so acclimated and introduced the shrimp test subject.

Soon the red cherry shrimp also began acting sluggish and unhealthy, just like the blueberries. Since water quality according to standard tests (ammonia, nitrites, nitrates, phosphates, pH, temperature, etc) all came up normal, the tank water must be getting contaminated from something abnormal within the tank itself. So I sat down I began searching for signs of possible contamination in the tank. The plants were common to many of my tanks and were doing well in other locations. The substrate was from the same batch I used in my thriving 2.11 gallon lace java fern tank – even from the same rinsing, so was not the cause. The filter had been seeded in another tank, which showed no signs of distress when it was in place. The filter media came from a different successful tank too, so the filter and its contents were probably not the cause. Suddenly my eye caught something I had not noticed before – small bright yellow patches on one of the rocks in the foreground.

Notice yellowish coloring on the rock in the far background, near the reddish shrimp. This coloration hadn’t been present when I first placed these rocks in the tank!

I removed the rock this morning, and hopefully there will be a change in their behavior. Though I had soaked the rock in water for about a month before adding it to this tank, it seems to have some sections that react within my tank. The remaining rocks show no coloration, but I might consider removing them as well if the shrimp still aren’t active. Since these rocks are the only element of this tank unique to this setup, if something is leeching chemicals, it is most likely them. Hopefully this works!!