Dubia Nymph Growth

[FlamingSwampert]

I received 24 Blaptica dubia nymphs during the November of 2020. I heard that it may take 5-8 months for them to mature, but they are still around 1/2 inch. They are kept a bit colder than recommended because the heat mat will only fit on their final, larger tank. I feed them an assortment of veggies and fish food pellets. They have a 1 inch deep substrait (zoo med's creatures substrate mixed with some ground-up leaves) and 2 bark hides (bark from a tree in my backyard, one peice is curved and has space underneath to hide, they love it), as well as a twig and a mesh climbing structure. They are active at night and readily gobble up their food.

Is this just the speed that they normally grow, or am I doing something wrong?

 

[Smiley]

In my experience, they should be growing at least twice that fast. A cheap ($12-$15) seed starter mat works great to get high 80s.

Does it really matter if your mat is larger than the bin they're in?

 

[FlamingSwampert]

In my experience, they should be growing at least twice that fast. A cheap ($12-$15) seed starter mat works great to get high 80s.

Does it really matter if your mat is larger than the bin they're in?

I will get a zoo med creatures heat mat, but I can't use it with their current container. It is a 4 1/2 x 4 1/2 x 3 (inches) container. It is circular, and so the heat mat cannot be attached to the side (you can't put it on the bottom, bc the roaches will dig down and cook themselves). Is the size of the enclosure too small(since they haven't outgrown it I figured it still is big enough, but maybe they need to be in a bigger enclosure to grow)? And other than heat (it will reach high 70s soon inside), could anything else be causing the growth problems? 

Edit: I have sourced a larger container and today I moved them in. The largest roach is about 2/3 inch. Most have been putting on weight well. I'm hoping that the larger space and more hides will allow them to grow larger.