Can I pour this over old concrete if I removed 90% of the thin set? Also, why can this not be used as a final layer? I was going to stain and seal it

Hi Kimp, It would be Sika's recommendation that additional effort is made to mechanically remove the remaining 10% of thinset, which represents a potential source of bond inhibiting loose particles and dust. Good sound field judgement should be exercised when preparing a concrete floor surface to receive Sika Level products. Sika Corporation recommends against installing Sika Level [PRO SELECT] Cementitious Self Leveling Underlayment as a final layer or wear course. It is recommended that after sufficient cure, the underlayment is covered by a substantive finished floor system (e.g. carpet, wood flooring, luxury vinyl tile, ceramic or porcelain tile, etc.). The finished floor system should have the ability to absorb and/or resist impact. Although any customer is free to do whatever they'd like to do with the products, a customer who only stains and seals sufficiently cured Sika Level [PRO SELECT] Cementitious Self Leveling Underlayment proceeds at their own risk. Please be advised that Sika will only honor the products' warranty when published recommendations for using in an indoor, temperature stable environment (i.e. conditioned space) and covering with an appropriate finished floor system are followed.