[germanblueramlover]

In the last 2 days I have noticed my red cherry shrimp acting a little strangely - standing still around the tank. When they are active they seem totally normal - busy picking little bits off the plants, swimming around, very enthusiastic about being fed!


I did a little research and found a few possible causes, but I wanted to post here to see if anybody can spot something I've missed or think of anything else I should check for.



It's a 10 gallon tank that was set up December of 2018 and houses only red cherry shrimp and a single small nerite. The only addition was 10 new cherries purchased from someone on here to add genetic diversity - they were added in either March or May of this year and had absolutely no issues. I use treated tap water with Salty Shrimp GH/KH+ and RO to top off. Temperature was running 23 C for most of the tank's life; I removed the heater 2 days ago when I realised it was mid summer and actually heating the water! The tank now runs around 22.5 degrees (it's hot here!).



Here's the 4 possible causes I found and my thoughts on each -

1) Low dissolved oxygen
I think this is unlikely as nothing in the system has changed, except slightly lower temps which should hold more oxygen. I have 2 sponge filters and I feel my surface agitation is good; there is minimal bacterial film or scum on the surface. The tank is half open at the top too so should have good circulation.



2) Bacterial infection
Again I think unlikely as I have not had any deaths (unless they were very sneaky about it). From what I can see nobody looks cloudy, although they mostly have good red colour and so their shells are pretty opaque.


3) GH/KH in a bad range
I tested these tonight and got GH 5, KH 3. This is I think a good value for cherry shrimp, and is where I've been aiming to keep my numbers as long as I have had them. This one is more of a contender though since I am a bit lax about testing here - I rely on mixing the same amount of shrimp mineral each time and keeping track of water change water vs RO top off amounts.

Additionally, I've fallen a bit behind on their maintenance recently and let the tank run at a lower water level than it should be, but that's been true for a few months now with no noticeable issues. I did a 10% water change 2 days ago and with that, I did bring the tank back up to its correct level - so I suppose this could have caused a shift in the GH and maybe upset them? I'm not sure though since I used a drip acclimation line to refill the tank so the addition of the top off water took over 24 hours, which I think should be enough to allow for a slow adjustment. Also, any shift would have been from higher GH to lower, which I believe is supposed to be easier on the animal.


4) Iodine deficiency
This could be it, if I rule out all the other options. I'm going to be taking a sample of my water to my LFS tomorrow to run their tests on it, and if all comes up clear there, I'll get a small bottle of Seachem Reef Iodide to supplement with.



Other than the standing still, everyone seems healthy and happy enough, so I don't think it's anything too severe! Thanks in advance for any help or insights you might have

 

[germanblueramlover]

Well, apparently our tap water is running high on ammonia currently. The tank sample tested 0 for ammonia so it's been processed already but I'm guessing the water change caused a slight spike which was just enough to upset the shrimp?

 

[Discusluv]

Well, apparently our tap water is running high on ammonia currently. The tank sample tested 0 for ammonia so it's been processed already but I'm guessing the water change caused a slight spike which was just enough to upset the shrimp?

That would certainly do it.

 

[mfgann]

I'm just getting into the shrimp keeping myself, but I believe this is why you will see many seasoned shrimp-keepers using RO/DI and remineralize with Saltyshrimp GH/KH+ until they hit the parameters they keep their shrimp in. This way everything will be consistent every time and you don't have anything you don't know about creeping into your tank.

We just picked up RO/DI water from the LFS today for the first time.. it was only $0.67/gallon. We'll probably purchase an RO Buddy in the near future and make our own.

 

[Tiger15]

I don’t know what standing still means. Do you mean the shrimp are inactive certain time. If the shrimp are well fed, they may take a rest sometime and don’t need to be actively feeding 24/7.

Using RO or distilled water is the safest way to keep and breed shrimp, because you take the uncertainties out of tap water. You don’t know what’s in the tap water unless you test for everything. Many tap waters pass through iron/copper plumbing with lead /zinc soldered joints and can pick up harmful metals to shrimp.

 

[Zoidburg]

I think the OP means that they are unnaturally standing still... alive, but "frozen" in place. They aren't actively moving their feet or eating.... just unnaturally standing there.


I use RO water (grocery store - water machines) and minerals for my shrimp tanks. I don't do this because I'm trying to rule out issues with tap water (well, besides the fact that I have converted a tank over to active substrate, so tap water isn't ideal in that tank... and the other is a brackish water tank, aka RO water and saltwater), but because I have to add minerals anyway since I have soft water to begin with... so if I have to add minerals, might as well just use RO water!

 

[en7jos]

Well, apparently our tap water is running high on ammonia currently. The tank sample tested 0 for ammonia so it's been processed already but I'm guessing the water change caused a slight spike which was just enough to upset the shrimp?

Seems many water suppliers are "modernising" by switching to chloramine for disinfection rather than chlorine. Chloramine brings several issues:
- chloramine contains ammonia, so a big water change can mean a big ammonia spike
- not all dechlorinators remove chloramine - check the label carefully!
- some cheaper RO systems (e.g. RO Buddie) do not remove chloramines - you need to add an additional stage to the filtration

Not sure if this is in anyway related to your issues, but worth bearing in mind. You should be able to check on your water supplier's website and view a water analysis to see if chloramines are being used. Dechlorinators like Seachem Prime remove the chloramine and detoxify the resulting ammonia for 24-48 hours which is hopefully enough time for your bio filter to process it. But in a shrimp only tank with low-level biofiltration, it may take longer to process after a big water change and hence the ammonia can re-toxify once the Prime wears off.

Seachem make a free ammonia alert thingy that stick on the glass inside your tank and lasts for 6 months. Something like that might be worth looking into?

 

[germanblueramlover]

Seems many water suppliers are "modernising" by switching to chloramine for disinfection rather than chlorine. Chloramine brings several issues:
- chloramine contains ammonia, so a big water change can mean a big ammonia spike
- not all dechlorinators remove chloramine - check the label carefully!
- some cheaper RO systems (e.g. RO Buddie) do not remove chloramines - you need to add an additional stage to the filtration

Not sure if this is in anyway related to your issues, but worth bearing in mind. You should be able to check on your water supplier's website and view a water analysis to see if chloramines are being used. Dechlorinators like Seachem Prime remove the chloramine and detoxify the resulting ammonia for 24-48 hours which is hopefully enough time for your bio filter to process it. But in a shrimp only tank with low-level biofiltration, it may take longer to process after a big water change and hence the ammonia can re-toxify once the Prime wears off.

Seachem make a free ammonia alert thingy that stick on the glass inside your tank and lasts for 6 months. Something like that might be worth looking into?

I'm actually really surprised we have ammonia since my city uses chlorine, not chloramines (unless they are doing things without telling us...)

I use Prime already! So I guess that's been protecting me previously; the shrimp have less frequent changes than the fish so this must've been the first change for them since the ammonia situation started. Someone in my local aquarium group reported an ammonia issue in her tap water the day after I did my water changes, too.


I'll be switching the shrimp over to purely using RO now for sure. For the fish it's not feasible for me to buy that much from my LFS, so I'm looking into either a small RO system to use at home, or else aging the water for a week with an ammonia removing chemical media. Thanks for the tip about the RO Buddie, I'll do some more reading to see what I'd need to get to process chloramines. It doesn't sound like my city plans to start using those currently; they're talking about using chlorine only and expanding their use of activated carbon and biological filtration.

 

[en7jos]

Thanks for the tip about the RO Buddie, I'll do some more reading to see what I'd need to get to process chloramines. It doesn't sound like my city plans to start using those currently; they're talking about using chlorine only and expanding their use of activated carbon and biological filtration.

I can save you some Googling if you choose the RO Buddie route (which I can recommend as I bought one myself a few months back and it works great, easy to install, good instructions, cheap replacement filters, etc, etc).

With regards to removing chloramines....

Read this: https://aquaticlife.com/blogs/news/chloramine-a-virulent-adversary

Buy this: https://aquaticlife.com/products/in-line-kdf-85-catalytic-gac-cartridge-for-chloramine-removal

Kind regards, James

P.S. If you have ammonia in the water, from whatever source, just remember that Prime only detoxifies it for 24-48 hours (according to Seachem). So good to re-dose Prime daily (or thereabouts) for a few days after water changes to make sure it stays non-toxic until the bio-filter has chance to process it.