you may add females, but more likely than not, they will breed. You must be prepared for that. Make sure your tank is big enough, 10 gal per gecko or so. You may introduce females of the same size, so w/ your 4 yr old, they would have to be full grown. Make sure any new gex you get go through a sufficient quarantine period, so you don't contaminate your boy w/ any new diseases. Make sure you have enough hides, and you will prob need a laybox, even if you don't plan on keeping the eggs. Without one, your female may retain them and become eggbound, which is serious. Introductions of new females to a male generally don't create too many problems, but as always, you must be prepared to seperate them at the first sign of fighting. Good luck!
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1.0 Hypo stripe, Het RW from JL (BJ)
1.0 HypoTang from Crested (Apricot)
1.0 Tremper Albino from Petsmart (Cloud)
1.0 SHCT hatched by me! (Sunny)
0.1 Hi-Yellow Leopard gecko from Petco (Beatrice)
0.1 Stripe female (rehabilitated rescue)(Pepper)
0.1 Jungle het RW hatched by me! (Jungle Bunny)
0.1 Normal from 2001 (Freckles)
0.1 SHCT Leopard Gecko from Petco (Brite)
0.1 Tangy Mutt Leopard Gecko from Petco (Rainbow)
0.1 Stripe poss. het RW hatched by me! (unnamed yet)
0.1 RW Stripe hatched by me! (unnamed yet)
RIP Peaches, Ghost, Bill
Adopted out: Goldie, Leucy, "Q"
Hatched: ~50