I learn't my lesson recently. This is to never ever pick up a Clarius Cat fish with your hands. The blooming thing spiked me with one of its fins and my finger swelled up to nearly twice it's size, thankfully I wasn't wearing a ring. The other lesson I learnt at the same time is to never answer a corded telephone whilst filling your tank with the hose. (Before anyone shoots me down on this comment, I have been doing this for 3 years without problems, I attach it to the sink in the kitchen which is a mixer tap so am able to get hot and cold running through and have never had a problem) Did this to answer a call from the NHS Direct helpline about swollen finger and whilst on phone tank overflowed leaving me with a massive puddle on my carpet. 
