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You may need to drink more during the day. Making sure you replace what you sweat out.
Has anyone taken a look at your running technique? You may be doing something differently when it flares up.
Also work up and down stream of the knee when mobilizing.
The Basic Leopard Kit is a great place to start. Lacrosse balls (tape 2 together), resistance stretch band, and rumble roller are used a lot. You can add additional gear as you find you need it. Voodoo floss is another common tool used. There are 2 different types red and black. The gemini and supernova (there are 2 sizes) are great resources to add when ready. Differences between the bundles are the number of items within each.
Hope this helps