http://aqadvisor.com/ is a great site for understanding how much capacity your tank is suitable for and how much filtration is needed for your stock..
I ran your set up through it and see the results. This is a 10g tank with 3 ACF and 20g of filtration as you can see, it is grossly overstocked and inadequate.
Everyone makes mistakes though I understand but please do upgrade as soon as you can for frogs sake!
Recommended temperature range: 20 - 24 C. [Display in Farenheit]
Recommended pH range: 6 - 8.
Recommended hardness range: 5 - 20 dH.
Warning: You NEED to add more aquarium filtration capacity!!!
Your aquarium filtration capacity for above selected species is 47%.
Recommended water change schedule: 93% per week. (You might want to split this water change schedule to two separate 73% per week)
Your aquarium stocking level is 191%.
Your tank is overstocked. Unless you are an experienced aquarist who can meet the maintenance/biological needs of this aquarium, lower stocking levels are recommended. [Generate Image]