I had a large quantity of pond stone that I used when I was keeping Mbuna. I had taken it out and was storing it in my parents garage, when they decided to use it to weigh down a tarp on a large pile of soil when they were doing some landscaping this summer. By the time I found out what they had done, the city had already sprayed for mosquitoes and tent caterpillars in our area. I'd like to use the stones now in my Red Devil's tank. If I clean the rocks with bleach and rinse them really well will they be safe to use, or do I need to scrap them and get new rocks? Thanks in advance for your advise.