As to the Exact cause of your Pumps, this varies greatly with the Individual.
I don't get the Pumps on Dbol or Anadrol.
But I do on Tbol and Anavar.
But since Blood Flow and Pressure do increase.
Any Deficiency in Magnesium/Potassium/Sodium can manifest itself into the Pumps.
Taurine's Claim to Fame is it's ability to help Lower Blood Pressure.
It's Vital to the Proper Functioning of Magnesium/Sodium/Potassium.
And since most people are Magnesium Deficient.
Taurine and Magnesium together help to relieve Stress/Calm the Nervous System/and aid in Sleep.
Plus, Taurine helps with Insulin Sensitivity, along with quite a few other Benefits............................. JP
P.S.
The Cialis is adding to the Pumps, as it increases Nitric Oxide.
One of it's Side Effects is Lower Back Pain ~ ie. Muscle Pumps.
Make sure you are drinking enough Water Daily ~ a Gallon to a Gallon and a Half.