Yamato crowd at filter inlet

[lwm999]

I'm using an internal filter. I put in 20 Yamato Shrimp in my 2 weeks old 3-ft tank last night. Today I saw the Yamato (as many as 15) crowd at the water inlet of the internal filter. Anyone knows why?

Thanks.

[|squee|]

For me, mine crowded there because my apisto was eating them up one by one (I didn't know that at that time). I asked Mr Chan of NA about this. He replied by saying it's usually the water that causes such behaviour.

Right now they're probably still adjusting to your water condition, or something in your water is not quite right.

[lwm999]

For me, mine crowded there because my apisto was eating them up one by one (I didn't know that at that time). I asked Mr Chan of NA about this. He replied by saying it's usually the water that causes such behaviour.

Right now they're probably still adjusting to your water condition, or something in your water is not quite right.

Hi Terence,
For your case, how long before the behaviour goes away?

[vinz]

This is usually the behaviour of yamato shrimps when the water is not to their liking. They might also hang around near the top of the water (clinging to the highest object in your tank), climbing out (e.g. drift wood that sticks out of the water).

Since your tank is so new, chances are there it's ammonia or nitrite poisoning. Or CO2 levels too high (if you are injecting CO2).

Are you running a canister filter? An internal filter might not have enough bio-media to allow a good population of good bacteria to grow in fast enough to handle the bio-load. Unless your plants are growing fast, they might not be able to handle the ammonia fast enough either.

Any other live stock in the tank before these guys?
Are you running a high light tank or a low light tank? CO2? Amount of light?

[vinz]

Oh, if I'm right and you don't fix the problem within 2 days, chances are you'll lose most of them.

[lwm999]

Vincent, thanks for your info.

I'm using 2x30W + reflectors, so not high light. There are a few Zebra Danio, Oto and SAE, all look normal. Don't know about CO2 ppm as using ADA soil, hard to measure. Have plants throughout the tank, although not very densely populated. So far one shrimp casualty per day.