I used a tinted blue color Drylok, it sealed the pond good for about 5 years and then I had to recoat it. I made the mistake of using any old waterproofer (forgot the name) on top of the drylok for super waterproofing it, and it wasn't made for moving water, like my waterfall...so needless to say the following year, the whole pond bubbled and peeled and my whole stock of koi died. I found plastic particles throughout the pond water. So, yes the Drylok works and worked good for about 5 years. But do not just put any old waterproofing plastic/latex on top of the Drylok or even on the concrete itself because some are not made to withstand waterpressure like from a waterfall and my pond cracked and bubbled and I had to strip the whole cement pond with a wire brush and reapply the Drylok. If you look closely at the pic, you can see all the scrapings on the bottom of the pond from that liquid plastic I had to strip.
