# shrimp deaths (nearly entire population)



## a1Matt (22 Jun 2009)

Last week I could see something a bit odd with my shrimps but could not put my finger on it.
Then some symptoms appeared in my snowball and green shrimp... their colouring went opaque and then faded, they started moving about more slowly. Then after a few days they were just lying on their backs and a few hours later were dead.  Happened to just a couple, so I thought it would pass. Bad thinking!

A day later my 9 amanos were all huddled in one cluster 2 inches from the top of the tank, and yesterday they were on their backs on the substrate, then by evening most of them had died, and more greens and snowballs passed away.

probably only have a few shrimp left in the tank now (I had a small population to start with).

My 3 dwarf cories are active as normal, but their colouring looks a bit off.

I guessed I have some 'toxicity' in the water. 

Yesterday I realised I had made a schoolboy error. Whilst my tetratec ex 1200 foam prefilter and filter itself were clean the flow from it was almost non existent.... the spraybar outlets were heavily clogged up. I added lots of emersed plants recently that were undergoing transition and shedding some leaves, so I guess this would have also put a strain on the filtration, probably enough to 'tip it over the edge' so to speak.

What have I done to try and fix things? (overdue) basic maintenance really...

I did a WC (50l of RO. tank is 160l).  
Removed the spraybar, flow is restored!
Gave the filter and pre foam a clean.
swished all the dirt up in the tank (there was loads! more than I have seen for years and it did not really show until it was in the water column).
added some activated charcoal\carbon to the filter.

I can not see what else to do other than keep swishing the dirt up so the filter can catch it all, and clean the pre filter every day to keep the flow absoultely tip top.  and a water change if I swish a lot of dirt up.

Any input gratefully recieved.


----------



## mr. luke (22 Jun 2009)

Im guessing your c02 level is normal? Sounds like low oxygen content or too much c02 going by the 'huddled near the ssurface' part


----------



## a1Matt (22 Jun 2009)

Thanks Luke.

I do not add CO2 to this tank, so it is not too high CO2. 

I had thought it could be copper posioning or more likely an ammonia spike causing my problems. I had not thought about low O2...

What looked strange to me is that they were huddled near the top, but a good inch or two from it.  They were huddled real close as well.  Which in itself is odd behaviour for them. If it were fish they would more likely be gasping at\or makng darts towards the surface than huddling and sitting below the surface.  I do not have much srimp experience though... is what I have described a typical shrimp reaction to low O2?


----------



## mr. luke (22 Jun 2009)

Shrimps tend to either 'surf' in the water flow or gether near the surface of the tank so it may be los o2.
When i had copper in my tank the shrimps flitted about the place in jerky motions then colapsed


----------



## a1Matt (23 Jun 2009)

It is to early to say for sure, but I think that now my flow is back on track my remaining shrimps are going to be OK, they still look a peaky colour, but are moving around normally now. FIngers crossed I still have enough left to get a colony established.

So I think you could have been right with it being low O2, as that would have been fixed by the flow improving.
Then again it would also have helped the filter to reduce any ammonia (or copper via the activated charcoal) so who knows!
Main thing is that things are looking up   

The difference in flow is incredible, and I can't believe I did not spot this until my shrimp started dying.  I guess it is because the flow would have been dropping off really slowly over a period of a year or so so I did not notice it.  That is no excuse though... I won't make that mistake again   

I am happy to air my faults on a public forum as it may help someone else who has similar issues brewing!


----------



## mr. luke (25 Jun 2009)

glad your tank is on the mend


----------

