I'm believed the brand of Cosrx from Korea is quite popular in Malaysia now. Then I feel interesting to try another product that related to blackhead which is Cosrx BHA Blackhead Power Liquid (100ml) with the price is RM 72.00; that's I was bought through the Hermo website. I do admit I have blackhead, especially on the T-zone.

The Cosrx BHA Blackhead Power Liquid is made to prevent the formation of blemishes before it happens, with a light texture, it works with your skin over time to soften and clear your skin with whitening effects for a more even skin tone. The BHA Liquid is a chemical exfoliator, contains 4% of Betaine Salicylate (PH Level 3.5 – 4.5). It exfoliates dead skin cells and impurities which are trapped inside in the pores. That's something manual exfoliators can't do. Removing the dead cell is important because it will improve the skin's overall health and appearance. Furthermore, exfoliating allows your skin to better absorb the other products in your routine and help them do their job more effectively. Generally, Acne occurs when skin produces an excessive amount of oil and dead skin cells. BHA liquid exfoliates penetrating deep inside of pores to removes dead skin cells and unnecessary oil, and it also prevents oxidized sebum from turning into blackheads. 

The BHA Liquid can be used 2 – 3 times in a week is recommended. BHA liquid contains 4% of Betaine Salicylate, so it's not suitable to use every day. It's great for oily skin type, rough and dull skin. The BHA liquid can be used with a cotton pad. In that way, you can remove impurities in a better way, and since it is a chemical exfoliator, then don't recommend to use directly with your hands. Just use it 2 – 3 times in a week. It can be used as a spot treatment. Apply the liquid on the cotton pad and gently buff your oily area (T-zone) and then tap gently to absorb it well. Then move onto the next skincare step. As for the Vitamin C product, each product may behave with different vitamin C content. The Cosrx product, Vitamin C20 is at a low pH level which is around a pH level of 3.5 and has a high exfoliating function. So it may irritate the skin by using BHA liquid at the same time. Therefore, they recommend you to use it every other day or use it on the problem areas after applying vitamin serum to the entire face. 

The BHA liquid with AHA 7 Liquid, since both of them, are in low pH level (approximately 3.5) and high-functional chemical exfoliators, they don't recommend you use them at the same time. But if you want to use it, they suggest you use it every other day. They also recommend using it in the morning or in evening. If you want to use it every other day due to the skin issues, they suggest using it 20 minutes after applying AHA7 or use it as a spot treatment. The BHA liquid with AHA/BHA Toner, BHA Skin returning A-sol – AHA/BHA Toner contains 0.1% of BHA and AHA, and A-sol contains 1% of BHA and AHA, so they're really mild product. Therefore, it's good to use them with BHA liquid at the same time. Since BHA had penetrating property, so they don't recommend using them during pregnancy and breastfeeding. It has water-like texture, or slightly thicker than water. They don't add any fragrances, so it may smell BHA's characteristic smell but it fades away soon. 

So far, this product is okay and fine to me. But the result does not show what's did I expected from it. It's just mild to remove blackhead on my face and it still has the blackhead on my face, especially in the T-zone area. I would like to give 3.2 stars of 5 stars to this product.