It really doesn't matter whether you were to use artist tube acrylics or the liquid, they are going to need to be applied at a point where the color depth is built up, instead of just trying to get all the depth in one application such as the creme pots can deliver.

You may need to lay down an underlayment first. This will help with any sheerness and you might not risk running into seepage of to much on the brush.
I would recommend folk-art brand or tubed acrylics.
good luck,

Thanks decorativewalls for the info. Could I ask you a question please? What do you mean by underlayment?

mrsgym,
you mentioned the paint was thin and way to sheer. I don't know what brand you may have been using or the color you are wanting for the backblash; but underlayment is when you need to block out the object underneath that you are wanting to paint over. Say for instance there is a big bright red vase and you want to paint a big green apple in front of the vase.
It may take several attempts to get a good solid coverage for the green apple but by blocking out the image you are trying to cover up - you will get there in the first attempt. I like using a color called "Taffy Cream". The color is by Americana crafts. It is a solid "opaque" yellow. Very good blockout coverage. The key is using a good opaque color and I find this yellow has worked great for me over the years.
Hope some of this helps.

The oil cream paint pots, I only use them for architectural type shadings or for shadowing other things. I use the ones by Deco-Art. Boy, those little paint pots can create a total mess if not handled carefully. I guess I am speaking of using these in my customer's homes. I need to be extra cautious.