Rotifers cling to the glass in the larval tank

[pszemol]

Hi,
I have a problem, I keep clownfish larvae in a 5 gallons ALLGLASS tank and feed it with rotifers. This is my first time so I do not have a lot of experience yet. What I have observed is that a lot of rotifers stuck to the walls of the aquarium and to the bottom instead of swimmingin the water column. Does this happen to me only or you saw the same thing ? If so, what causes rotifers to stick to the glass ? I have not big water movement in the larval tank, due to the swiming abilities of the larvae, maybe this is part of the problem ? But what attracts roifers to stuck to the glass? in the first place ?

[Kathy55g]

What salinity do you culture the rotifers, and is there a great difference between that and the salinity of the rearing tank?

Rots can tolerate some rapid salinity changes, but if it is too drastic a change, they will not do well, and collect on the bottom. Joyce Wilkerson says that a change of greater than .007 specific gravity is too much.

[Kathy55g]

I am not very experienced, though, so you should wait to hear what the others have to say.

[rsman]

most of what joice says is true enough, but thats NOT rotifers can handle much higher swings than .007 with no ill effects. when i feed my reef i go from 1.012ish to 1.026 with no issues.

my first guess without more info (come on pszemol i know u know better ) is that those are copepods not rotifers, rotifers have nothing to hang on the glass with. however bad lighting will cause rotifers to crowd the glass.

[mano]

I've seen rotifers congregate on the sides of my tanks with seahorse fry in them but these are kreisol type tanks so that is probably why. As long as the rotifers are still alive I don't think it's anything to be too concerned about. Get a magnifying glass and see if you can see them better.

[mattydub]

Originally posted by rsman
however bad lighting will cause rotifers to crowd the glass.

why? There's no reason for rotifers to care about light...or so I thought...

[Atticus]

I agree that they are more than likely pods.

[rsman]

why? There's no reason for rotifers to care about light...or so I thought... well your right and your wrong all at the same time doesnt it make you feel good

in the wild light is very important, light is where the algae hang, algae is a high limiter on the amount of rotifers that can grow in the wild, so they do hunt out light, however your rotifer culture is not the ocean, your culture should never be food limited, and algae should be plenty, they dont need light to see the algae, they need light to allow them to know where the algae is in the watercolumn, in your water column the algae should be all over, because of that they can find food by opening there open mouths

[pszemol]

These are rotifers, not copepods. I checked with my stamp loupe, 10X magnification.

They do not look very alive - maybe dead or just weak ones get stuck to the bacterial film collecting on the glass?

Not sure about the reason, but I do not want them on the glass, I want them in the water, where larvae can eat them.

BTW - my maroon clowns larvae is one week old now, it has greatly improved swimming abilities over this week. Still black coloration and this "peanuts in the shell" shape of their body :-)
Tomorrow I will start feeding freshly hatched brine shrimp for the first time. I have read in Joice book this is difficult moment for the youngsters. Oh, one more thing - I made them a picture and counted them to be about 130 alive. This much left from about 650 eggs after one week period. It makes about 20% survival ratio at this point. Of course I know this is not the end of deaths...

[ediaz]

Maybe your tank is "dirty" like mines. I ussually have to "scrape" rots off the glass before I siphon the tank. I am not sure if they attach to the glass but do a count of rots, then scrub the rotifer tank walls with your hand, count again, the count will be higher.

In the larval tanks I seen the larvae feeding off rots from the walls.

If the concentration in the water colunm is good , then do not worry about clinging rots.


Ed

[chico_andrade]

Hi all,

In my larvae tanks, sometimes the rotifers hangs in the walls, but observing a single rotifer, I could see that after some time hanging there it went to the water column again, I also saw larvae eating the rotifer in the wall.
Chico