hi i have a cubicus boxfish and have got home from wrok today and have notied that he is just sitting on the sand bed this is not normall behaviour he is normally swimming around eating bits n bobs of the rock. i have checked all of my levels and they are nitrate 10 nitrite 0 ph 8 amonia 0. salt is 1.022 i am due to do a 10% water change tommorow and i have the water mixing and warming up as we type lol. this is the first i have noticed him being sick anyone no if this is a sign of bad things to come or weather it is normal behavour every once in a while ??