Hi! The tank you've got is PERFECT, if you're following the 10 gal/30cm per axie rule. The question is do your axies look happy? Do they have lots of hides? Are you happy with water conditions and the number of water changes you have to do?
Don't believe those who scream "BAD OWNER" for having a tank that isn't massive. As long as the tank is well cycled, cooled and has plenty of hides, three axies can happily live (Without nips, bites, etc) for months in a 45cm long tank (the ones who were in there have since moved out to my big tank thanks to my chiller crashing). I currently have a 4 ft tank which has 6 axies living happily (No intentions of going higher in there.).
A better rule to follow with tanks is :
1. Can they swim around, turn around easily, go up for air, have plenty of walking area?
2. Can they hide away if they get peeved off with someone?
3. Can the filter hold the biological load of the tank and are you comfortable you will be able to do the water changes religiously?
If the answer is yes to all three questions, you're good. Then ask:
4. Can I afford the space for a bigger tank?
5. Can I afford the cash for a bigger tank?
If the answer is yes to 4, then you get a bigger tank (Even if it means a few weeks in a big bucket or a holiday in the fridge whilst you save religiously).
Good luck with your babies!
