7 year old trivia question on how water features worked 2000 years ago...credit doesn't go to cement mixes, they leaked plenty. The secret is they had a continuous water source. Aqueduct, ditches and even pipes diverted water from streams at higher elevation, ran into fountains (no pumps needed) and then out of the fountain into maybe a bath house and then thru a sewer and on away from the city. So it was OK for stuff to leak some. Curious to hear how the wax thing worked out. Best sealer I've found is no sealer. Liner covered with concrete or mortar. Has never failed me and is super cheap and easy. Pretty hard to mess up. Allows very reliable pipe penetrations. I also prefer the look of aged concrete so that can be done too. Sealers require stable concrete. Different sealers can span some tiny cracks but even hairline cracks can cause failure. Which is why swimming pools and professionally built concrete ponds and water features are so thick and use so much steel. Concrete over liner only needs 1" or so of concrete and no steel (steel is bad in this case). If the outside of the fountain is to be visible you create in a standard way, thick and steel. Then liner and another 1" of concrete. Only you will know there's a liner.

Slabs have been acid stained. Smaller pours have been pigment in the mix itself. Using test batches with the formulation carried through to the final pour, you can pretty much guarantee the color will be right on with an integral pigment. Acid staining, it can be hit and miss. You can get an exact color match or you might have to tweak what you get with touch-up applications of stain, as there are so many variables in the formulation, finishing and aging process of the slab. Consider an epoxy film finish and then topcoating with wax. Waxing is optional.

I have concrete floors w/radiant heat in the kitchen/dining room, not stained, just a sealer applied. I also have dark acid stained floors in the living room with radiant heat, a passive solar house- in the winter sun light comes in 23'. The acid stain has held up 15 yrs, but now showing some effects of the UV rays, color is definitely lighter where the sun left it's mark. The unstained kitchen has held consistent color (same sun exposure) and just now requires resealing. My wish is we had not acid stained the LR. Best guess is it will hold color another 3+years before an intervention..... & no clue how/what that will entail. My kitchen, however, is good to go, the gray patina improves with age, (& a lot of imperfections ) ,still looks good from kids, dogs, NY winters & a ton of traffic. Paint is not a good choice for longevity. Acid staining is the only way to go (it penetrates the surface) but it is a mess to deal with- prep work to protect walls/trim, wash down (with lots of water), foot booties, safety glasses, gloves, face masks & the result is a 'live with what you got' situation. Good luck.

Don't do it! If you want "texture" go with a high-end stain+epoxy finish with the LOOK of stamped (some of these guys are ARTISTS who LOVE to create a "look" using stains and etchings...some of them will get a "wood texture look" with just stain...truly stunning). If you are going to have "finished" concrete floors, you need to tell the concrete slab guys BEFORE they pour, not after!!!! They will need to revise their estimate to INCLUDE a high-end concrete finish = micro-topping. They can do this....so long as you TELL THEM. Don't spring this on them AFTER the darn thing is poured. Your cost will go up astronomically. And I'm not kidding on that. Poured concrete for a slab is NOT ready "to be finished". Too many people believe they can save money by finishing their slab as "concrete flooring". They find out (later) they were wrong. That "finished" concrete is EXPENSIVE. More expensive than a decent laminate+labor ($4 + $2 /sf). A finished concrete floor is a LIFESTYLE choice (ahem...$Mill homes, condos, etc). They are stunning. They are expensive. And they are often covered up (by regular home owners...not millionaire homeowners) inside of 7 years. Why? Because they are HARD to live with (hard on the feet, ears, etc). Ask yourself why you want finished concrete. And then ask the concrete people how much they would charge EXTRA to prepare the slab for "finished concrete floors". I think you will be surprised by the up-charge.