Neocardinia Deaths

[Bjorn]

Discovered a neocaridina death this morning and another this evening. They were both lying on their backs, fully intact and motionless. I got them as part of a 10 piece variety pack from Aqua Huna 19 days ago. They arrived in 72 hours and all seemed healthy on arrival. I placed them in my community tank and started the medication trio (first time for everyone). Observing them, they seem to have been adjusting well, constantly grazing, coloring up, and growing impressively fast.

I've only spotted two of the ones that are alive today. I watched them carefully and it didn't seem like they were grazing as much as I've seen them though it could be me projecting my concern. I'm a bit stumped and disheartened. I haven't changed anything since I've gotten them except gradually increased the CO2. But I doubt that's the culprit because my drop checker hasn't read anything close to dangerous. I run an air stone to be on the safe side. Plus, the first death happened early in the morning before CO2 was on.

Maybe copper  some other toxin has gotten into my water somehow? Should I get a test kit? My city's water report tested 0.12 ppm Cu so contamination would most likely have to come from something other than my source.

Water Parameters:

Ammonia: 0.0 ppm

Nitrite: 0.0 ppm

Nitrate: ~10 ppm

Ph: 7.2 (3hrs post CO2 shutoff)

dKH: 7 (3hrs post CO2 shutoff)

dGH: 11

Temperature: 79f

 

 

[Cory]

What fish are in the tank? 19 days isn't a long time to have them. How low the the pH getting during the co2? What size is the aquarium? What is the water change schedule? Frequent water changes can be hard on shrimp.

[Bjorn]

@Cory Oh nice. I got the g.o.a.t. to reply.

On 12/13/2021 at 10:37 PM, Cory said:

What fish are in the tank?

Male half-moon beta, guppies, cardinal tetras, and otocincluses. I know the beta seems a likely suspect but I doubt he's to blame. The tank is a 37 gallon and based on observing his temperament with guppy fry he's too lazy to chase anything that won't swim directly into his mouth. Maybe he's been lucky lately? Potentially but I doubt it and the dead shrimp were in one piece.

On 12/13/2021 at 10:37 PM, Cory said:

How low the the pH getting during the co2?

I'll test and update tomorrow during the next cycle. I haven't tested peak saturation in awhile since I've been trusting a drop checker.

On 12/13/2021 at 10:37 PM, Cory said:

What size is the aquarium?

37 gallons

On 12/13/2021 at 10:37 PM, Cory said:

What is the water change schedule?

10-30% weekly. Today (day of incidents) has been 6 days since last water change.

[JettsPapa]

How long has the tank been running?  I've not had good luck with introducing shrimp to newly setup tanks.  They need biofilm to graze on pretty much continuously, and that takes time to develop.

If that's not it, then the CO2 would be my next guess.

[Aqua junky]

what is your BBS on your co2?

 

[laritheloud]

I honestly doubt it is something of huge concern. Sometimes neocaridina species can be a little sensitive with a tank/parameter shift. The way I lost the fewest shrimp (I actually lost none from that batch) was to buy them from another hobbyist and drip acclimate over a couple of hours. I also purchased a few from my LFS, and a couple of those did die over the first three weeks or so.

I wouldn't be terribly concerned about it unless your entire population dies off. It took about a month for my shrimp to berry and breed in my tank, but once they started, they took off. Focus on smaller water changes if you can for a little while and wait and see. Changing something/messing with parameters might do a little more harm than good for them.

I don't really know much about CO2 in shrimp tanks because I keep my neocaridina in a low-tech setup, but if you're not pushing the limits, it's probably okay. BUT on the tanks where I do run CO2, I err on the side of caution and don't go anywhere near the max threshold of CO2 injection, and I'm still very pleased with the growth and lushness of my plants.

If it's a newer setup, you could try something like glasgarten bacter ae to encourage biofilm growth and feed the shrimp.