I Have a 190ltr 3 year old tank and have had two percula clowns cleaner shimps a fire shrimp snails, red leg hermits and several corals these have all been in the tank some time with no issues apart from loosing the odd snail here and there. Every time i introduce a new fish it dies
some last a few days some a couple of weeks i have tried blennies cromis gobies a wrass a flame angel a coral beauty and a tang all to no avail any ideas on what is going on. I have tried baiting out to see if there is any preditors in the tank but have had no joy and have heard or seen any tell tail signs. thought the o2
level in the rockwork could have been low when the fish rest at night so i aireate the water when i do water changes to ensure the o2
level stays high. I Have just introduced a pair of torpedo gobies and the clock is ticking ANY IDEAS ??????