Hey guys. As a lot of you know I have and Oranda goldfish. She is in a tiny 10gal tank which I have always hated for her. Well now I have in my hands a new 25gal tank for her. Only problem was it was used and has calcium.lime build up on the glass. It needs a good cleaning but I dont think a bleach and water bath will be enough for this. Is there any cleaners anyone can suggest?