Rick,
Not very easily. I would have to drain it, remove the sand, remove the bulkhead/neoprene/silicone, and redo it. It took 2 weeks for the silicone to dry the first time.
This just simply exposes another flaw in the system. As much as I like the swimming pools, it is just not a good idea to try to put a bulkhead through the bottom of them.
For those of you wonderingââ"šÂ¬Ã‚¦.the pools are holding up exceptionally well. I have not noticed the slightest bit of color fading or brittleness in them. It seems as though the polycarbonate panels on the greenhouse are blocking the UV that you would expect to damage the pools over time. I am very pleased with the poolsââ"šÂ¬Ã‚¦.enough to probably use them again in another outdoor system. I mean, come onââ"šÂ¬Ã‚¦$10 tanks that are the perfect depth. It doesnââ"šÂ¬Ã¢"žÂ¢t get much better than that. I would just put my plumbing through the sides of the tank next time. The sides are reasonably flat (except for the curvature) and you could repair a leak better than on the bottom.
Over all, I am not upset with this scenario. I wanted this greenhouse to last for 2 years, and it may still. I am learning a lot from this and I am going to drag it out a little longer. This just gives me an excuse to start planning #2.
Redoxââ"šÂ¬Ã‚¦.Iââ"šÂ¬Ã¢"žÂ¢ve had trouble reaching you by email. Give me a shout sometime so we can talk about those fiberglass tanks you are using. I might need about 8 of them. (sorry everyone for the personal communication on the thread)