I found it . Sorry went to chat and they or one said from the hood . It was the filter which is part of the hood ,not level and was running down back of tank. Its so dirty as I took all the media out to sort it. Put most of it back. Tried to vacumm but well I've now left it to settle . Put the clean water I had stood to get to room temp and added dechlorinator will check Nitrite levels and add clean water. Boy what a panic Friday night too.Thanks
