I recently went on holiday for a week, leaving two holiday feeding blocks in my tank. it said it fed 20 fish from 8 to 10 days so I thought they would be alright. I get back and the feeding blocks have clearly dissolved revealing pellets, which they were meant to do, but my fish weren't looking too good. all of them had lost their colour and the neon tetras were grey and floating about rather than swimming happily. I quickly put in some flakes and only one of my platies was eating. after several attempts, I got all the fish eating and the next day, their colour was returning. does this always happen with holiday feeding blocks? was it the change of food that made them unwell?
I'm now uncertain about what I should use next time I go on holiday. is getting some1 round to feed them a better idea?