I don't know if I'd have a rock big enough, the patch ended up being about 4 x 4, and the divot is about 6 x 6. The vacuum is just the standard one that everyone originally buys, the oval-y shaped one on the end of the pole with the brush underneath. We hadn't vacuumed the pool yet when the tear appeared, I'm embarassed to admit we hadn't vacuumed for the first time until last week. But the pool was still very clean inside because we were barely in it and we run the filter. I'd like to get the Hayward Wanda the Whale vacuum next year. Can the vacuum we already have cause us problems until then?

I'll look up how to do a dye leak test. I'd like to find the leak, the patch seems to be holding fine. I was in the pool for the first time since the patch the other day and it looked good. But we're losing about an inch a day and I'd like to find any leaks.