Juvenile Axolotl Help

Hi Guys,
I have a juvenile aaxolotl, not sure how old it is or gender but it is about 9cm long.
I was wondering if I would be able to introduce sand substrate to the tank yet?

I was also wondering if I would be able to get it a friend? The tank isn't very big, but I'm planning on getting a 3 ft tank or bigger. Would it be okay to get a friend about the same size and have them together in the small tank for a little while?

Thanks in advance for your help!!

Probably best to wait until your axolotl is at least 5 inches (13cm) or so before adding sand.

How big is your current tank? Axolotls grow fast so it may be better to wait until you can upgrade before adding another axolotl depending on the size of your current one.

The current tank i have is 50cm long, so about 1.6ft. And my current axolotl is about 9cm.
I'm hoping to get the new tank in a week or 2.

Probably best to wait until you have your new tank and get the new tank cycled.

Okay, thank you!
How do i cycle the new tank?
And when i do eventually get another axolotl, will i have any problems with putting them together? I have read that sometimes they wont get along and they might nip each other mistaking them for food.
Will i have any of these problems if they're both young and around the same size?

Do you have a testing kit? If not, you should invest in one. I would recommend the API liquid freshwater master kit. It is pricey but lasts a long time and necessary for maintaining good water quality for aquatic life. Below are a couple of links on cycling which would be good to read.

Scales Tails Wings and Things, What is Aquarium Cycling? How to Cycle your Tank

The link below is a guide on fishless cycling method. It is your choice whether to use this method or cycle the tank with your axolotls in the tank. I prefer to use and recommend the fishless cycling method as I believe it is far easier and doesn't potentially expose aquatic life to potentially harmful levels of ammonia or nitrite. If you do decide to cycle the tank with your axolotls, you will need to be very diligent in frequent water changes and testing to ensure that the levels of ammonia and nitrite are at safe levels (should not go above 0.25ppm).

The (almost) Complete Guide and FAQ to Fishless Cycling - Aquarium Advice - Aquarium Forum Community

Now, given you are not familiar with the cycling process, until your new tank arrives, you should get the testing kit and test the parameters in your current tank. You can post the readings here.