Thank you for allowing me to assist you, my name is Joe and I will be happy to assist you with your concern today.
Streaking/color running is a condition of the actual paint/pigment and if running this indicates a problem with it itself, this means that to resolve the problem would require a protective coating over the existing, however with it already chalking this means you usually first have to sand the surface and restore color by either gelcoat or paint then a clear in some cases however in this instance you are dealing with an inflatable which is a pigmented fabric material and requires a different approach as you may be aware already.
There are cleaning products such as : http://www.polymarine.com/advice/inflatable-boat-cleaning-finishing-guide/
But know if it is painted then the problem is chalking of the paint which would require repainting, you also have the option if not painted to also paint them.
What you are experiencing is usually due to a lack of proper maintenance and or age of the material esp in direct sunlight and heat esp extreme heat.
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