You know that chromium plating process already knows as on my old article and mention about bright chromium plating for the process. Actually there is chemical to make the result really can produce bright chrome plating if we adding brightener agent into the bath chromium plating, without brightener in the solution you won’t get bright result. I have tried many time by variate the voltage and electric current but without brightener, the result won't bright. One of the product may can use as on the picture below.
Reprochrome Brightener is use as chromium plating brightener. The price of this product is about $10 per 4 fl oz. The chromium bath solution that use this product with formula 0.4 fl oz per gallon to get the bright plate.
For the brightener agent use in electroplating process may be vary but I just have example one, you can looking in the chemical shop about this product, or you may found other better product that I give you.