stubborn roaches, can't kill them!?

The Combat gel is all you need. The site tells how it works. They are immune to spray and can mean they are german roaches.

The problem is that you're using all of these methods at once. Typically the most effective method of getting rid of roaches yourself is by baiting them by putting the gel and roach bait stations in areas with high roach traffic. Since you sprayed, the roaches aren't going to be attracted to the bait anymore, since it has been contaminated with spray that they tend to avoid. The ortho spray you used is long-lasting, so it will have residual effects for a while.

If you want to continue with the spraying method, you should also get boric acid powder and dust it lightly in places where roaches might be finding food so that you've cut off their food source. Also make sure to spray outside so that the roaches won't come back once they've left. Bengal does make a newer spray called Bengal Gold which has an extra additive to keep the roaches from breeding. I used it in the places the exterminator didn't spray and it seemed to work.

If you want to bait, try to clean the areas where you've sprayed and place new gel and bait stations around. Keep in mind, the roaches are SUPPOSED to walk out of the bait stations. It is a slow-acting bait that kills them within 12-24 hours. This gives them time to go back to the nest, where other roaches eat their poisoned excrement and eventually their dead body when they die, killing other roaches as well.

Give it some time; nothing will kill them right away, but be diligent in getting rid of them, don't leave them any food or water sources, and you'll be rid of them in a few weeks.

Get a small bottle of boric acid at the drug store, or a large bottle of Roach-Pruf at the hardware store. Take a small amount on the tip of a spoon and blow it in the general direction of any place you have seen a roach, any crack in a baseboard, and under sinks. Not in open floor areas or cupboards. The powder sticks to a roach's shell and dissolves the waxy coating so they dehydrate. They carry it back to the nest and pass it around and it wipes out the entire nest. One application is usually enough.

Get lizards... 5-10 can clear a roach problem in an average house in a matter of a couple months.. They eat the roach eggs, with each generation fewer eggs make it to hatching, until there are no more roaches.. Be sure to get several lizards so you get at least a few of each sex so they can breed giving you more egg eaters...

Bengal Gold Roach Spray

Try borax powder. Its a soap. Spread it behind washer, dryer, stove, fridge, places like that. Remove the back cover of your stove/oven. Its warm and dark there so they lay there eggs there. Clean it all out. Use roach bombs. Spray spray spray and kill every roach that you see.

Oh wee buddy I think you need to call an exterminator.....lol they must be immune to what you're using.