Advice on an attribute module needed

Hello,
New to opencart and was wondering if I could get some advice on an attributes module needed. I need opencart to be able to handle stock counts on multiple attributes. For instance, say I was selling food coloring in different sizes:

Say I have two bottle sizes on a product:

10ml
30ml

I also have three colors:

Green
Red
Yellow

I need a module where I can set the stock counts individually for each product:

10ml Green
10ml Red
10ml Yellow
30ml Green
30ml Red
30ml Yellow

So basically I need an Add-on that can allow me to set the stock counts on the different bottle sizes and colors individually. What would you recommend?

Thanks in advance.