shrimps dying - experts help needed.

[rocketshrimp]

Hi,
Need the shrimp experts advice here.. I have been keeping shrimps for a while, but till now, I am still very puzzled to why my shrimps die. This morning, one of my crs died

My observation is:
1. It usually happens during the night, and the next morning, I have to do a casuality count.
2. Most of the dying shrimps don't show any signs of stress.

My current setup is
1. chiller at 27-28.
2. MH light (about 6-7 hours)
3. heavily planted tank.
4. PH 6.5, fairly constant I think.
5. No predator fish. only rasboras and otos.
6. Shrimp load is medium.
7. CO2 count at 2 bubbles per sec. (on 24x7)
8. Top up water once a week...(about 2% only)
9. Fertilization is low (dose once a week...now trying once in 2 weeks)

Could it be due to the lack of oxygen during the night? Plants give out oxygen in the day right? and CO2 at night...if so, what to do about it?

Would appreciate any advice.

Thx.

[vinz]

I don't think it's lack of O2. Could be CO2 overdose at night or a pH swing due to higher levels of CO2.

Usually a decently planted tank should have enough O2 to last the night, if you give them enough lighting duration to photosynthesise. At night they consume O2 stored in themselves before consuming O2 in the water.

Do you buffer your tank pH with KH? If not, add some KH using bicarbonate of soda or baking soda (not powder). But measure your KH first. The recipe is in a sticky that I will put in the beginner's forum in a few minutes. In your case, since you do not change water, you should only have to do this once. If you do a major water change, then just add back what you changed out. (i.e If you need 1 teaspoon initially, and you change 50% water, add back 1/2 teaspoon of baking soda.)

At this point you can wait a few days to see if the situation improves, or do the following as well. I'll suggest waiting since your fishes seem not to be affected.

Try the following for a week or so, and see if your shrimps still die off at night. Turn off your CO2 when the lights are off and on when the lights are on. If you are using DIY CO2, then get an airpump and aerate the tank during the light off period. The aeration will help to bring the CO2 levels down. It will keep the tank oxygenated at night as well.

[BFG]

Me 2cents.

Try lowering your temp to 26 or better 25 deg. I'm keeping mine in a 2ft with 25 deg temp with a chiller.

[rocketshrimp]

Hi Vinz,
Thanks for the excellent suggestion. I have a somewhat tall tank (2x2x2), so it might be that the 02 may not absorbed well enough for my tank. Will try to setup a timer to aerate my tank when the light are off. For KH, I do not keep track of it. The last I measure (some months back), it was at an acceptable level. I will re-measure that again.


Hi BFG,
For temp, I think that while shrimps are happier with lower temp, within 27-28 is ok. I have seen tank without chiller and the shrimps are doing fine. (eg. look at mermaid's LFS tank). I was advised not to have the temp too low as the offsprings of your shrimps/fish will not be able to survive in another tank w/o a chiller. That's if you are intending to sell/give away your shrimps/fishes that you breed.


Thanks all.

[wf7850]

thou Mermaid doesn't use chillers for their tanks, the entire shop is airconditioned and with the fans blowing 24/7, the temp is lower as compared to those natural ventilated areas.

anyway, i have been keeping shrimps for almost two years and found that they will just die for no particular reason. we dun mentioned bout mass death which may be caused by huge pH swing, high nitrite levels, pesticides etc, but one death 2day and another 2molo is quite common. i never pay notice to such deaths with the other shrimps (ie. cherries, yamatos, tigers or bees) but when it comes to CRS, it is abit heart pain as they cost considerably more.

My CRS had started breeding so meaning water parameters are good and favourable but I have also noticed that one adult is dying each and every week, and yes, they always die at night. i have since remove all pumps and CO2 to my CRS tank and leave only an air pump running a bio-sponge filter. only taiwan moss in the tank which is reputed to grow without CO2.

will monitor and see if any improvements (ie. any more deaths at night)

[BFG]

I have been told that the lower the temp (up till 25deg) the more eggs the shrimps can carry.

[rocketshrimp]

wf7850,
What you have described, is very similar to my situation. We belong to that not so newbie category ...and yet the shrimps are still dying. I must have like spent couple of hundreds on shrimps already (enough to have a very good lobster meal)...not to mention all the peripherals that I put in place just to hope to keep them alive. (everyone thinks I am mad...house no aircon, but fishes have..) Now, with the keeping of CRS (who can resist them? they are very "singapore" kind of shrimp...red and white), the stakes are alot higher, hence I better get to the kung fu level (9?) so that I can have a high degree of confidence of keeping them...else I will give up all together and go keep guppies or something.

What vinz had shared, sounds like a good possibility....(why didn't I think of that? ).

BFG,
Thanks for sharing that tidbit of info. Very interesting..didn't know that.

[wf7850]

...else I will give up all together and go keep guppies or something.

haha.... my feeling exactly too....!!!

anyway... will let u kno if the measure i took was effective.

[Crazy Dragon]

Hi,

I have also started keep shrimps about 2 months ago and I faced with the same problem, except my tank setup is very much simpler (just java moss with air stone).

Somehow after adding in the ketapang leave into the tank, the death rate slow down tremenously until no death (within 2 days). I believe that this leave plays a part in stablising the water.

Late last week I shifted the shrimps to a bigger tanks and combining all my different type of shrimps together. This time the tank setup is abit more complicated (with graval, java moss and some other plants) I do not add CO2 but with air sponge filter) The most important thing I added upfront is a piece of ketapang leave and till today, no death and the shrimps are happily molting. The leave is still in the tank and most of the times, I see a few shrimps on the leave. I am not sure if it is truely the effect of the leave but as long as no death I am happy. Just my 2 month's experience, just to share.


regards
Crazy dragon

[rocketshrimp]

Hmmm....Hmmm....Hmmm...

What do you know...no casualty today. All I did was to turn off my CO2 last night after the lights went out. This morning, when the lights are on, you can see the grin on the shrimps faces. Let's see if this will last for then next few days. (rushing out to buy a CO2 solenoid... )

Crazy dragon,
As for the leaf, yes, I am using that too. (to bring down my ph). I use those sold in packet form by the branding "miracle leave"..(cleaner I think). Yes, I agree with you that that is one of the key ingredients to keeping shrimps. (It is a wonder what a little rotting leave can do for your tank) Thanks for sharing.

[lorba]

I am not a shrimp expert, but don't you need to keep the water a little hard to keep them healthy? Like adding calcium to make their shell tougher?

Acidic water should kill them pretty soon.

[rocketshrimp]

Hi Lorba,
Yes, shrimps need calcium, but I think that they will have to get from the food. The recommended PH for shrimps is around 6.5, especially for bees. (that's why a lot of people have trouble keeping bees). I feed my little critters with some food that I got for $15 per standard fish food container.
That's mighty expensive I would say....but hey, they are my babies. Now you know that I am a certified shrimp-nut also.

[vinz]

Hmmm....Hmmm....Hmmm...

What do you know...no casualty today. All I did was to turn off my CO2 last night after the lights went out. This morning, when the lights are on, you can see the grin on the shrimps faces. Let's see if this will last for then next few days. (rushing out to buy a CO2 solenoid... )

...

Hope I'm right! Is this the first time you have zero shrimp casualties in the morning?

[rocketshrimp]

Not the first....some days, I am lucky....let's monitor this for a few more days. But I think my CRS just smiled at me....

Thanks.

[rocketshrimp]

Just to update:

I turned off the co2 for the first 2 days - it worked.
Thereafter I put an airstone without turning off the co2, it also worked. So, it is either to stop saturating the water with co2 (c02 poisioning) or to aerate the water (introduce 02 to the water and also to disperse the co2 in the water).

At first, I wanted to get a solenoid...but to my shock, it will cost me 100+, and also will have to get a timer. I figured that the cheaper way would be just to run a airstone (still have to get the timer). The wastage in co2, I think it is very little.

Now I am motivated to get more CRS ..big thanks to all who helped me in the forum.

[wf7850]

well..... guess wat..... since removing the CO2 and replacing the internal filter with the air-pump driven bio-sponge, there has been no further casualties. The remaining shrimps' colour seems brighter than before and they are more active rather than the usual hiding under the DW.

One of the female that had gave birth even showed signs of carrying eggs again....!!!!!

[rocketshrimp]

That's great, William.

Myself, this morning...one tiny weeny shrimp died. Hm..Seems that CO2 is the definite killer here.

I am now considering if I should do the co2 solenoid thing...rather then just operating an air filter.

[vinz]

Stick to the airpump... it's cheaper.

If you do want to get a solenoid, spend a little more (about $120, but I'm back-dated on prices nowadays) to get a decent one. There are a few not so good ones out there. And shop at the more reputable planted LFSes.

[Sims]

Hi,
My current setup is
1. chiller at 27-28.
2. MH light (about 6-7 hours)
3. heavily planted tank.
4. PH 6.5, fairly constant I think.
5. No predator fish. only rasboras and otos.
6. Shrimp load is medium.
7. CO2 count at 2 bubbles per sec. (on 24x7)
8. Top up water once a week...(about 2% only)
9. Fertilization is low (dose once a week...now trying once in 2 weeks)

me not expert but 2 cents worth,

ever heard people using shrimps to test co2. co2 is a prob but why u on it 24x7. change the light timing to suit the time u r home and on the co2 since u are using manual.

chiller change to 26C

don't top up water. change it.

try planting some hornwort. or use nitrate ammonia remove stuff

hope it helps

[rocketshrimp]

Hi Sims,
Thanks for the suggestions.

I have my co2 on 24x7 as it is troublesome for me to keep turning it on and off. It is ok if I am not keeping shrimps....however, on hind-sight, my otos died mysteriously also...must be the co2.

Vinz,
Airpuimp don't seem to work too well...this morning another casualty.. ..think I better get that co2 solenoid.