Need feedback on rebuilding tank
This is a tricky (but fun!) hobby to get a hang of, which is why I need feedback on my next project. Firstly, I'm already having to sterilize my plants, b/c I didn't know enough to sterilize them before placing them in my new tank, and I ended up with snails. I used the diluted bleach method, since I couldn't find potassium permaganate anywhere - I submerged the plants in a half-filled 11 liter bucket with a splash of bleach for two minutes. I'd previously removed two snails from the tank, and I discovered two more in the bucket after I'd finished with the soak. I considered this a good sign, so I soaked the plants in another solution of water and dechlorinator for 35 mins, then used the diluted bleach solution again, this time for one minute. I'm currently letting the plants soak in water and dechlorinator for an hour. Having to do this has got me thinking about changing the substrate in my tank - from gravel to sand.
I've already purchased some playbox sand to use in the future when I finally set up my 10gal, but I've been researching methods to exchange substrate in an already-established tank. I'd like to keep some of the original gravel on top of the sand. I've read that this is an ideal method, so that the benificial bacteria from the old substrate can begin to colonize the tank, again. So, this is my planned course of action, but I'd like to hear from anyone who's ever switched substrates in an already-established tank. Any further tips??