pH: Definition and measurement units. pH is a measure of how acidic/basic water is. The range goes from 0 - 14, with 7 being neutral. pHs of less than 7 indicate acidity, whereas a pH of greater than 7 indicates a base. pH is really a measure of the relative amount of free hydrogen and hydroxyl ions in the water. Water that has more free hydrogen ions is acidic, whereas water that has more free hydroxyl ions is basic. Since pH can be affected by chemicals in the water, pH is an important indicator of water that is changing chemically.
sealing a cinder block wall. I just finished sealing the cinder block wall in our basement with Baer waterproofing paint. After the first coat I noticed little orange rust colored spots in one corner of the room. Nice fresh white coat of paint, little spots the size of peas on one wall.
Masonry paint (also called elastomeric paint or elastomeric wall coating) is a good choice for concrete painting because it contains binders that contract and expand with the concrete. Exterior house paint can crack and peel on concrete. Masonry paint ($20 per gallon) can be tinted and is much thicker than exterior paint. Apply it with a masonry brush ($5 to $8), a high-capacity (3/4-inch or higher) roller, or a texture roller ($5.50).