So long as your mix is properly balanced then you can just cut the PPM down by adding some water, then pH and use it.
As to PPM's, this is only important as it relays an overall strength of minerals in the solution. Plants generally start getting pissed if you have an EC greater than 2.4 (thats 1200 PPM) depends a lot on the grow and strain. All that matters is the total PPM and the balance of elements.
Remember that the "PPM" your meter is displaying is simply a representation of the electrical conductivity of the solution. It is not an exact PPM (mg/l). Some bottles like the micro contain elements that are more conductive to electrical charge and therefore the difference between actual PPM (mg/l) would be greater than a bottle the bloom.
The effect is also not always liner. So if we add 1 ml of a product to a solution that is at say 200 microsiemens (or 0.2 EC or 100 PPM @ 0.5 conversion) and it jumps the conductivity by 50 µs (25 PPM) we might see that adding 1 ml to a solution that is already at 2000 µs only raises the total by 20 µs or we may see a rise of 80 µs.
So in short, the EC measurements we take with our pens simply relate an overall conductivity. You could have a solution thats strong in nitrogen but only 800 PPM burn your plants where a more balanced solution at 1200 PPM doesn't burn them. An over abundance of one element can be a problem as well as an over abundance of the whole.
To better understand your nutrients checkout this thread
Understanding and Calculating Nutrient PPM PPM (Parts Per Million) can seem like a mystery but it’s actually very simple. Basically the idea is to quantify how much “stuff” is in your water. PPM is commonly measured by a grower using an electronic pen which measures the electrical conductivity...
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