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The usual guideline is that the food should be around 1.5 times the width of the body and leave a visible lump in the belly after feeding for 1-2 days (the rule no longer applies nce they reach adult mice, which will be the largest food most Corns need). It looks OK by that measure. Very important not to handle for 2 days after any feeding though, or you do risk a regurge.
We advise not handling or feeding for a week after you get it, so that it has time to settle into its new home and doesn't get stressed. Probably best to start the 7 day clock from now.
There are some FAQs stickied at the tops of the individual board sections will will hopefully answer some of your questions, but I think we'd need to know a few more specifics to help you
Here are my Top Tips:
- Make sure the tank is escape-proof. You won't believe the tiny gaps they can squeeze through.
- Temperatures are important. No more than 90 on the floor at the warm end, preferably around 85. Most heat sources will need a controller to keep them cool enough. The general kit used by folks here seems to be an undertank heater (UTH) on a thermostat, but some use overhead lamps with dimmers equally successfully.
- At least 2 hides, one at the warm end of the tank and one at the cool end. In reality, as many hides and as much ground cover as you can get in there, to make the snake feel secure. The hides need to be as enclosed as possible, so they can tuck themselves in there and feel hidden from predators.
- Bowl of fresh water at all times at the cool end (to keep condensation down), big enough for the snake to curl up in if it wants to. Replace it every few days, or immediately if pooped in.
- On food the size in the photo above, I'd feed one every 6-7 days. An exact schedule isn't important as the snake won't know when it's feeding day.
- If the snake spends a lot of time in the water bowl, it's usually either too hot or has mites.
- Corns are active in the wild at times of low or no light - dawn, dusk and overnight, It's normal for them to stay hidden away during the day.
- If you provide water, they will drink. You'll just rarely see them do it, so don't be spooked by that.
- Before they shed, they go a slightly lighter colour than usual - called "blue". They then go back to their normal colours for a couple of days and shed after that. They can't see well during the process as they shed the scales over their eyes, so we advise not feeding or handling until after the shed.
- When they shed, check the old skin to make sure the eye caps and tail tip have come off. If not, you need to sort this out as soon as possible.
- Don't use wood from soft resinous trees like pine in the tank, as the sap gives off fumes which irritates their lungs and can cause breathing problems. Hardwoods and fruit woods are fine, as is cork bark.
Bit of a brain dump, but combine that with the FAQs and let us know if there's anything else you need to know