Well,these were the first (and only) salamaders that I bred. I had purchased both of the salamanders (male and female) at a pet shop in Houston, TX. Unfortunately they did not know the age of these but said they were captive bred. I kept both of them in a very large (100-gallon) aquarium with a mix of leaf litter and organic planting soil as a substrate. A quarter of the terrarium was an area with a pond sloping from 1 in of dept to 5 inches. I hibernated my salamanders by simply placing the terrarium outside from December to February (in Texas, the temperature drops into the high 60’s). After bringing the terrarium back in I created a rain chamber with a canister filter. The filter sprayed lukewarm water on the land area. In the wild this prompts migrations to breeding ponds. On the third week of March I discovered that there was a masse of eggs on a plant’s underwater roots. There were exactly 93 eggs in the masse. Unfortunately, only 70 eggs hatched, I collected the larvae and put each one in a small plastic container. The larvae hatch at about 13mm and they were extremely hard to feed, and 5 died. They only took live Bloodworms and tiny chopped blackworms. Within 3 months off hard work the young had begun to transform to the terrestrial stage at this point I moved them to larger 10-gallon terrariums (5 salamanders in each). I was forced to sell 50 of them, but kept 15. This was 3 years ago and now they may be able to breed (with another litter from a different family to prevent inbreeding). Eric .D if you do want to breed them you do not need a tank as large as mine, but the large the better. Remember some Spotted Salamander will lay up to 200 eggs, and most will hatch so you need a lot of space to raise the larvae.
Good luck with the Spotted Salamander, they make a great captive.