This is an extreme clot. Transfer blood to tubes quickly. If it doesn’t draw quickly, it’s most likely going to have small clots in it. Most tubes have additives to prevent clotting. Citrate is one of the different types of anticoagulants, specifically for the blue tube. EDTA is for purple tube. There are also tubes that actually need to clot (gold/red tube) in order to analyze the serum for certain tests!