cherry shrimp disappearing??

[Palinurus]

Hi

I don´t think, that diatoms are the reason for the problem. They only soil the panes or other surfaces. How long was that plant in the fish tank before? Plants sometimes are treated with poisons which only work with arthropodes (insects, crays, spiders etc.) but not with fish or snails. But after some weeks this poison should be washed out. I don´t think you will find the reason by knowing water parameters. May be you´ve got a clan with an invisible degeneration. Breeding with selection only by the outer appearance neglects invisible mutations, that lead to weaker, less vital individues.

Cheers
Wolfgang

[Robin]

Wolfgang, the plant I moved into the 6 gal with the shrimp has been in the other tank for at least 5 mos or so. I just moved it into the 6 gal 3 days ago. The shrimp issue has been going on for at least a month. I got these shrimp from a well thought of breeder; other buyers have been pleased with him...

Robin

[Ulli Bauer]

How old do you think the shrimp are now? For how long have you had them?
Could it be just an age issue?

There are so many reasons why shrimp can disapper...
Let me summarize (many have already been named above):

• predators: planarians (long, thick worms with a triangular head and two dots in their "forehead" that look like eyes); damselfly nymphs: look closely for stick-insect-like creatures with three tails, usually very well camouflaged; dragonfly nymphs: look like a kind of ugly thick beetle, also masters of camouflage. Best look for predators after the lights are out, with a flashlight.
• germs: do some of your shrimp have milky white, opaque bodies? Could be they're dying of a bacterial or fungal issue.
• insufficiently watered plants (can be ruled out, I think) and subsequent poisoning
• artificially covered gravel: may also cause slow poisoning of shrimp (I had a case when it happened after over a year )
• plastic tank decoration: might be colored with unsuitable colors containing lead, copper and so on, might also be the case of intermittent deaths
• Mopani wood has been known to emit stuff that's not good for shrimp, probably due to unsuitable sanding material
• low levels of anything poisonous in the water: copper, ammonia, pesticides, whatever - not enough to kill all at once, but enough to take out one after the other
• filter's clogged, subsequent accumulation of harmful stuff
• dead snail, fish, whatever lying around rotting
• too much food or dead plant parts, high numbers of bacteria in the water eventually leading to oxygen deprivation
• or.... .... ....

Hope this helps, it's always hard to stand by watching... Sometimes one has to check everything one by one just to exclude stuff.

Have you found dead ones, btw? Or could they just be hiding?

Cheers
Ulli

[RescuePenguin]

Robin,

My idea would be to feed them less at each feeding and feed them more often. I personally feed mine 2 out of 3 days. At the moment it seams to work well.


Steve

[Robin]

Hi Ulli and Steve,

Thanks for that information and I will definitely take it to heart.... Ulli, I have only found molted skins, never a dead body. I will definitely check further this weekend when I do a water change.... I'll keep you posted

Robin

[AdeDunn]

Water parameters can often be a very good way to detect underlying problems. For example traces of nitrite or high levels of nitrate can often indicate that there has been an ammonia spike (possible even in mature tanks with mature filters), or that you are overfeeding or undercleaning. pH can often indicate problems as well, and also be a problem in itself, too low or high for example could add to health problems with cherry shrimp. GH is another useful indicator, if it keeps going up and up and can indicate that you need to increase the quantity or frequency of water changes. Too low a KH and it can make it more difficult to maintain a stable pH, and so on. So although they might not tell you the cause of THIS problem, it's definitely useful to test.

Something else that may be useful would be to get a water report from your local water company. Knowing what they are putting in there for example can be very useful. A common occurrence for example is for nitrate levels in the tap water to increase, meaning that you are adding more nitrate with water changes rather than reducing it (one of the reasons I switched to using RO in my tanks). Water companies also often change the way they treat the water, adding things like flouride etc.

Something else to check, have you changed brand of water conditioner? Some water conditioners will react with traces left behind of others, and have been known to cause problems. By the same token, are you using fertilisers in their tank for the plants? Even those considered safe for shrimp can slow breeding activity down if dosed at high enough levels. If you are dosing, perhaps try reducing the dose a bit, see what happens.

This is the problem with the shrimp hobby though, sometimes it can be very difficult to find what's gone wrong if it has. As Ulli pointed out though, it could just be that your shrimp aren't sexually mature yet, or on the other end of the scale if they are full grown adult shrimp it could be they have actually reached their lifespan (on average about 18 months for most neocaridina, shorter in higher temperatures). A common occurrence is that people by adult shrimp because they want an instant colony, only to find out that they're all old folks who are about ready to pass, and is why I try if possible to make sure the majority of new purchases are juvenile or even baby shrimp.

Oh and one other possible cause I haven't seen yet is that of too many water changes. Water changes can often act to stimulate shrimp to moult, if however this is too soon after the last moult the shrimp isn't ready and moulting can fail. Try also to make sure they have plenty of calcium and iodine in their diet, this shouldn't be an issue if you are target feeding with good quality commercial shrimp foods. There's nothing wrong with feeding natural foods at all, however it's useful to supplement this with commercial feed which may contain things your shrimp need that the natural foods may not. A good varied and balanced diet is often key to a successful shrimp colony.

Ade

[Robin]

Hi Ade - great post...
I still need to check my water parameters. I have not changed the water conditioner I use and I do a water change every weekend. I know that when I bought these, it was noted that they are juveniles but I don't know the exact age....

Thanks everyone!
Robin

[Robin]

Oh - and I have put some egg shells in the tank. Now that IS the newest thing that has happened.... it has to have been maybe 3-4 weeks that they've been in there - that couldn't be a problem could it? I've got snails in there too. I do not fertilize at all in there for the live plants (probably should but I don't)

[Ulli Bauer]

Hi Robin,

any news?
I don't think the eggshell has anything to do with it (you cleaned it and removed the "skin" before putting it in, right?)...

Cheers
Ulli

[Robin]

Hi Ulli,

I did clean the egg and remove the "skin" from the inside. I didn't boil the egg...

I was at the LFS and surprisingly found some freshwater shrimp! I was so excited that I bought 2 red cherries.... They are much bigger than the ones I already had. However, since they've been in the tank, my others seem to be out more. I love it. I did a water change last weekend and found no invaders.... also less planaria have been noticed! I'll keep an eye on this tank anyway. Thanks

Robin