[Under Foot]

Hi Dana, and welcome to the NSRA forums!

There are many good products for cleaning natural stone. The real key is that it be a "neutral" cleaner (i.e. that is has a PH balance of about 7). It is good to hear that the stone has been sealed, as this will help. Please keep in mind that not all sealers are created equal, however, and that the best quality sealers can cost almost 10X less expensive varieties. If your installer sealed the floor after installation, I fear that it is unlikely that the sealer used was a high quality, vapor permeable one (it is that RARE installer that is willing to pay substantially more for a high quality product when the client doesn't know the difference).

In any case, keep in mind that stone sealers have an effective life of only about 1-2 years, especially on a floor that receives regular foot traffic. CheeseDog is correct in stating that it is beneficial to dust mop regularly (sand and grit on a floor will cause it to wear much more quickly), but you need not be concerned that weekly moping will create problems for you, SO LONG AS YOU USE A NEUTRAL PH CLEANER. A neutral PH cleaner will not leave a residue behind, and as long as the water used for moping is clean (as one would expect with regular cleaning), you will not be doing your floor a disservice (full disclosure: CheeseDog and I have slightly differing views on this matter).

It is unavoidable, however, that a porous limestone will eventually need professional cleaning (e.g. here in the USA there are services, such as Under Foot, with specially constructed steam cleaning units that can remove soil from the microscopic pores inherent in your stone...perhaps these services exist in the UK as well). Have your limestone floor professionally cleaned and resealed every 1-2 years, and it will provide you many decades of beautiful service.

Good Luck!