No it is is not an error, they will grow into there new homes.
Just make sure that the glass containers seal properly and there are no gaps that the spiderlings can fit through and get out.

Ok thanks guys. Just to make sure there won't be any negative side effects from keeping them in their new homes provides they are sealed properly? ( I would have moved them back but other half had already disposed of containers) Part of the fun for her is making pretty homes for the T's. Just a quick question how do you measure the tarantula's leg span? Meaning how do you get it to stay still long enough to get the tape measure or is it a case of estimating with the eye? Just asking so i know before moving them to bigger homes prematurely.

Vash1979 wrote: Ok thanks guys. Just to make sure there won't be any negative side effects from keeping them in their new homes provides they are sealed properly? ( I would have moved them back but other half had already disposed of containers) Part of the fun for her is making pretty homes for the T's. Just a quick question how do you measure the tarantula's leg span? just asking so i know before moving them to bigger homes prematurely.

Depends really. Some measure legs, some measure body. I go on leg span personally. As cascade said, they will grow in to their enclosures in time and as long as they have a place to hide then they should feel secure enough to do their thing.

Ok thanks. All the T's except the P.I. have a shelter made from egg boxes. the PI has got some bark that makes a crevice.

Vash1979 wrote: Ok thanks. All the T's except the P.I. have a shelter made from egg boxes. the PI has got some bark that makes a crevice.

The egg boxes are not the best hides/material to use for your spiders, especially with the moisture in the enclosures.
You can use a piece of bark, or not give them any hides, they will dig under the substrate, or you can take the top of 2liter coke bottle and cut gaps into that and make hides for them.

Ok will remove the egg box hides when I get home. They did seem to like them though. Especially the Lasiodora parahybana, Brachypelma boehmei and Acanthoscurria geniculata. Any idea for a home made hide for the Lasiodora parahybana, as I think it might be a wee bit to big for a bottle cap