why do you need a substrate for your locusts? if you have a raised bottom with circular holes in you can put cups full of vermeculite in (fine grade). then you gust need to take these cups out once every 2 weeks and put some new ones in and then put the egg cups under a 40w incandecent bulb and within a few days- up to a week or so they should be hatching. if you have more than one cage for locust you can have one for juveniles and one for adults. Only the adults will have the vermeculite cups because only they will be laying. when the locust start to hatch put the whole cup in with the small locusts. I'll take a few photo's of our setup if you don't understand what i mean. For grass you need to replace it 3x a week. you can just cut it from overgrown verges and should be 20-30 cm long- you can cut circular holes in the lids of plastic cups, half fill the cup with water and shove the grass in there and it should be good for 2-3 days. then you can feed them supplements of oat-bran if you are feeling kind. The easiest way to supply water i find, is to have a cup upside down with a few cuts around the rim- have this full of water and sitting in a deep petri dish. if the holes are below edge of the petri dish the petri-dish will fill up with water but not overflow- if you have a 300ml cup this should last a week or two. Again if you don't understand my explanation i'll take some photos for you. Of course you could always buy locusts off biosupplies if you can't be bothered breeding your own- the web address is http://www.ak.planet.gen.nz/%7Ebio/