Caridina japonica - dying reasons?!

[Marya]

Hi everyone!

I'm new to this site and I hope you can help me!

My planted tank was set up app. two months ago so it's quite new.
3x20 w bulbs (equals 3x100w), Daylight, tube is type 860, should be 6000 k
light is on for 9 hours
pressu. CO2, pH-controller set to 6.75
water temp. 22,5 degrees celcius (no heating)
drop checker always bright green
AquaClear hanging filter
1 ml TMG per day + 2ml macro per day (solution: 200 ml water+ 5,25 tsp KNO3 + 1,33 tsp KH2PO4 + 1,33 tsp K2SO4)
Substrate is Elos Terra with gravel underneath
40% water change every sunday

Animals are ? number of Caridina japonica (max. of 13), hopefully 10 CRS shrimps, youngsters, and then 11 Nanostomus marginatus. I've had all the animals for several weeks by now so they are fully acclimatised.


Here's a picture of my tank just to give you an idea of it. It's not updated; the plants are much larger and growing better by now and I've defeated the brown thread algae (Mougeotia I think) visible among all stem plants in this picture:
http://www.akvarieplanter.dk/forum/album_pic.php?pic_id=797


I haven't been able to measure any water parameters but will try to do so. My pH controller needs to be calibrated but I haven't been able to do so yet either. However, I have set the controller in such a way that the drop checker is (dark) green.

I've watched 2 amano shrimps die by now and probably rescued 2 by removing them to some fresh water while lying in cramps. The other shrimps normally always hide very well!
The strange thing about these dying shrimps is that the small CRS seem unaffected and this morning (when rescueing 2 amanos) some other amanos that I managed to spot seemed fine as well. And the fish have been fine and acted normally the whole time.

I've have spotted some small amounts of cyano in my tank and this makes me think that maybe high amounts of nitrate can be the dying reason? Or maybe it could be high CO2 levels?

Please help me out by telling me what could be the reasons for my shrimps' dying or by telling me generel reasons for amanos' dying.

Kind regards,
Maria

[Koi Boy]

for sure be careful with co2 set ups and shirimps
i have wiped out my share of japonicas by paying too close attention to the plants
over dosing fertalizers can kill shrimps easy
and nitrate should be kept low as possable
do you have carbon in your filter media? carbon is not the best for planted and shrimp tanks
how did you get rid of the hair alge? not chemically i hope coz thats a problem

[Marya]

I will check my nitrate levels as soon as possible and check CO2 too. No carbon and no chemicals used. I removed the algae manually and partly it disappeared by itself.

[southerndesert]

Be sure to check your Nitrite and Ammonia levels as well as Nitrates! Nitrite and Ammonia are much more critical and will kill shrimp very quickly if there is any reading much over 0

Good luck and do a water change...half or so may help as well.

Bill

[Koi Boy]

depending on the set up the oxygen level can be sucked out during the night period by the plants if the co2 is running consistantly during that time
some ppl like to turn off ther co2 at night because plants needs
o2 dring there sleeping time, depriving the shrimps of oxygen maybe
but it makes no sense to me that japonicas are dying off and not the other type of shrimps coz for all i know joaponicas are strong and robust shrimps
so i would question where the shrimps are coming from or how long have they been broken in befor you have purchased them
a lot of possibilities in the problems that your facing now
what i would do is let the aquarium break itself in a lil more b4 trying again with any new shrimps. IMO

[soulmanure]

I have to agree with southerndesert--with any new tank, the thing to keep a close eye on is your cycling. Your nitrites, nitrates, and ammonia should be kept at proper levels before the addition of any live creatures. If there are other reasons for the deaths, you can at least rule out cycling as the cause.

[TitoC]

I have to agree with southerndesert--with any new tank, the thing to keep a close eye on is your cycling. Your nitrites, nitrates, and ammonia should be kept at proper levels before the addition of any live creatures. If there are other reasons for the deaths, you can at least rule out cycling as the cause.



the only thing I have known Caridina japonica dying from, were sudden temperature changes (ie. throw shrimp in tank 5°C colder) and ammonia/nitrate levels.
Once upon a time I had some of them in a full Platy-breeding tank as the garbage patrol. When I shut down the filter to clean it, the shrimp were turning pink and dropping like flies within minutes! The ammonia cycle was only barely making it in the overcrowded tank and the shrimp were the first victims as the ammonia raised for a few minutes. I was already kicking my own ass and throwing away some of the 'carcasses' and luckily I was too angry to continue, because as the filter was running again, just as fast as they had turned pink, they cleared up again and went along their daily business as if nothing had happened.
My guess is that it takes a bit longer to really kill them, but I don't recommend trying this at home ;)
Of course, if it is the problem in your case, we're talking about a chronic rise in the levels. A diagnostic treatment with adding a cycled filter/ material from another tank should provide an answer.

As Koi Boy said, it is very weird the japonicas would get killed, and not the other shrimp!

If not for big shocks, Japonicas should live for years. The first I had were already adult when I got them and they outlived most of the fish, moving along from city to city with me. Finally the last one died after 6 years.
If you keep them in cooler circumstances with a few 'winters', who knows, they might even live as long as a small-sized dog...........?

[Marya]

Yes it is very weird that the CRS turned out to be so hardy compared to the amanos! But now everything's fine: I found out it that it was too high CO2 levels that killed the shrimp! Still can't explain why it didn't kill the CRS too though..!
thank you all for your kind and interesting replies :)

[NOVA]

Hey guys,
Sorry for waking up this old thread but there's some info here I think may help people which might not be contributed if a new thread were to be opened.

I have a planted tank for more that a year now.
Shrimp were for the most part breeding like crazy.
Specs:

240L
Filtered well..
0.9 W/Liter
CO2 at around 25-35PPm (24/7 though when I cut it during night-time they still seem to die..)
Nitrate ~ 20 (DIY)
Phos ~ 1.5 (DIY)
KH ~ 4
GH ~ 7
PH ~ 6.7
Temp ~ 26 C' (though problems started on winter time when Temps were 24 C')


I have managed to wipe out and entire shrimp population of regular denticulata shrimp and Japonica shrimp in a matter of a week.
Not sure what had changed.. Perhaps CO2, Perhaps Fertilizer overdosing..
Recent attempts to add a few more resulted in the same way.
I can't see how come they die on even with the tank being so oxygenated from the O2 pearling of the daytime..
Some of my friends suspect it's either Iron poisoning or Calcium deficiency.
What do you think of it?

Here's a video of a dying Japonica in my tank (and no, that's not how they look when scraping food).
Can you identify what causes it's death (mind the white-creamy look of it's body)

Edit: Apparently I'm not allowed to post URLs..
Could anyone please volunteer to post the link? I'll PM it to you..

Thanks.

[TitoC]

Hello Nova, sorry to hear about the frustrating problem.
Good that you provide detailed information.

Despite oxygen pearling off the plants, it might still be a lack of oxygen that gets to the shrimp. But then there should be little stirring of the water (likely if you are adding CO2) and usually the shrimp come to shout for help at the water surface. An overdose of CO2 could also be the problem, perhaps you should check the amount at night too?

Another possibility is that something is rotting in the tank (a dead plant, apple snail) and the toxic products are affecting the shrimp. But if it is a big tank with a good filter, it has to be quite dramatic.

Iron and CUPPER are also possibilities, but then you have to have added it somehow.

Calcium is also not very likely if you have a good tank for plants.

You didn't add new plants to the tank after which the problems started?

Is there anything you can notice on the shrimp? Black/brown gills? Black spots? Problems with molting?

Probably you'll only be able to pm after 20 posts. If you can list the tags to search for the video in youtube, I'll post it.

[NOVA]

Hello Nova, sorry to hear about the frustrating problem.
Good that you provide detailed information.

Despite oxygen pearling off the plants, it might still be a lack of oxygen that gets to the shrimp. But then there should be little stirring of the water (likely if you are adding CO2) and usually the shrimp come to shout for help at the water surface. An overdose of CO2 could also be the problem, perhaps you should check the amount at night too?

Another possibility is that something is rotting in the tank (a dead plant, apple snail) and the toxic products are affecting the shrimp. But if it is a big tank with a good filter, it has to be quite dramatic.

Iron and CUPPER are also possibilities, but then you have to have added it somehow.

Calcium is also not very likely if you have a good tank for plants.

You didn't add new plants to the tank after which the problems started?

Is there anything you can notice on the shrimp? Black/brown gills? Black spots? Problems with molting?

Probably you'll only be able to pm after 20 posts. If you can list the tags to search for the video in youtube, I'll post it.


Hey TitcoC, Thanks for trying to help!
Regarding CO2 Levels, I've seen once (long time ago, during night) how the shrimp would fly up to the surface to take a breath. If I recall correctly that was prior to the time when I injected CO2 24/7. At that time I only injected CO2 during photo period. After a while I added an oxygen pump during night-time. I'm not sure if I succeeded in achieving good oxygen conditions for the shrimp 'cause I didn't look to much for their bodies during the day..
Even though, I made a change a few days later (though I knew they were dying..) and switched to 24/7 injection of CO2 and used an external Atomizer which may have done too-good of a job.. I started seeing less and less of the shrimps..

So, I may have more than one issue which causes the mortality.

What's considered to be a dangerous level of CO2 in PPM? (I'd be happy if some folks with High-Tech tanks would also reply based on their own experience)


Regarding checking the CO2 levels
I did an experiment two days ago: unplugged the CO2 for about 36 hours. After about a day the PH went from 6.6 to 7.3. I then inserted some shrimp (plain Dent's and Japonica) and it seems as though they were suffering a few hours later and I conclude that based on their static behavior (which should normally be voracious) and their color which was milky-white (should be clear with blue-green-gray patterns).

In the morning most of them were dead. It may have been so because they were adjusting to a new environment OR suffering from another issue which I don't know of right now, and the night-time deficiency of oxygen only made it harder for them.

So that experiment weakens a bit the suggestion that there was a CO2 overdose.

Regarding rotting - I hardly believe it may be the cause. The tank has almost no dead plants. It's been worst before and the shrimp never mind that.

Copper and Iron: I can't see how I may have overdosed with Iron if I add 6 ML of Seachem Iron twice a week and get a few more drops from Seachem Flourish.. Also, refraining from Iron dosing didn't seem to help.
Copper - I don't add any more than what's in Seachem Flourish. I dose it twice a week, 6 ML. Other metallic stuff - That was a main concern which i've concluded on my own - something may have fall in and I don't know what it is or where is it but it's killing to shrimp. But... I've had a metal braced-net which held a Fissidens fontanus plant attached to some wood for a few months and it didn't seem to mind the shrimp.. It could be that the other metallic thing that fell, as opposed to the metallic net, disintegrates with time or that the net does but it took a few months for the amount in the water to get critical.
Anyway, the metal net is out now and I have made water changes of 15-20% each week so that should have kept the issue restrained..

Calcium: I may be entering a Calcium deficiency stage because I've been changing from tap water to 100% RO water during the past 8 months or so, with 15% change each week and have lower KH from 12 to 4 (GH is now around 7). People which advise on other forums say that for now it's still enough Calcium to prevent shortage for the plants. I see now special problems as well.
Could it be that though it's enough Calcium for plants, it's now enough for shrimp?

Regarding new plants: I've added so many I can barely remember.
The only plant which I know of that is bad for shrimp is Anubias which allegedly secrets something to the water after it is pruned which affects the shrimp badly.
Do you know of any other plants that may hurt shrimp?

A typical stressed shrimp in my tank would look passive, have trouble grasping the gravel or plants in order to walk around (looks like he's on his head) and have a strong milky color of the body. I can hardly see their sloughing anymore and I guess it's 'cause there aren't any shrimp left in the tank.

Tags of the video is P1110806. It's the second video and my nickname is MrPopocatepetl.

[TitoC]

http://www.youtube.com/watch?v=2InmYF2GX44

Indeed, this doesn't look like a typical death by lack of O2 or CO2 overdose. It does look like somekind of neuronal problem, possibly toxic / ionic.
The Calcium shortage could be tested by putting them in water rich in Ca. A big shortage can cause neuronal disfunction.

One good guess left, is still the introduction of a toxic plant. I've also heard the rumours about Anubias, but I'm sure there are more plants with a defense against arthropods...

Interesting but sad case... Hopefully someone can make some useful additions...

[NOVA]

thanks.
Anyone care to comment? Maybe saw a similar death in his tank?