ml> air bladder... it is what they use to keep their "balance"
and float 
ml> up and down in the tank... kinda similar to a scuba diver's weight 
ml> belt... it keeps them neutral in the water...

 SD> Sorry for the pleas on the BBS the other night.  I was genuinely
 SD> worried. 

not a problem... there are responses to them but they were made several
days late... no need to be sorry about looking for assistance ;)

)\/(ark