Is it soft and squishy? That can be due to over watering, but a picture would certainly help.

I will try and get a picture

Are you sure they are all the same variety? Varieties can have quite a wide colour range.

we have about 6 large plans now all from one original plant so all genetically the same. and hey have varying colours too. if the have been too hot/sun or cold etc that alters the colour in the plant. they do become uniform once the conservatory temp settles. the newer leaves are also paler in the ones we have.

In the case of Aloe vera itself--and I have seen all sorts of Aloe labelled "Aloe vera"--plants with a little too little light are usually a light lime green. Plants with good sunlight are usually blue-gray in color. With good light and coldish nights, they may develop an orangeish bronze color--which is their form of plant antifreeze. Lack of water or nitrogen will make them bronzey, also.