Affresh W10549851 Dishwasher Cleaner with 6 Tablets in Carton

Q: I don't have an odor in my dishwasher, but it doesn't clean dishes properly anymore. Would this help renew the efficiency?

No, the main interesting ingredient here is citric acid, which will remove the "hard" water buildup (calcium and magnesium minerals) from the dishwasher, along with anything odor-causing that's living in that buildup. The only thing that'll get your dishwasher cleaning dishes properly again is putting phosphate back in the dishwasher detergent (it was taken out by all the manufacturers in 2010 because some, not even all, the states banned it). You can either go through some contortions to buy sodium hexametaphosphate and add it to regular detergent or buy something like Bubble Bandit (which gets around the bans, even in those legislatively-misguided states, by claiming to be for commercial dishwashing machines) which still has plenty of phosphate in it. You could also try one of the fancy multi-compartment detergent pods (the highest-end Cascade as well as Finish Quantum, possibly others, but do your research for which ones actually work), but those are pretty expensive, especially since the different-colored compartments aren't just a gimmic (likeI, cynically, originally thought) but are actually supposed to release different chemicals at different times in the rinse cycle. Phosphates will both get your dishwasher cleaning again and prevent the buildup in the first place. Their removal from dishwasher detergents is a faux-environmentalism scam, as those contributed less to less than 1% of the phosphates in wastewater, even in those places where phosphate concentrations were a legitimate problem (which is not even everywhere). The biggest culprit is, unsurprisingly, industrial pollution, and that's, equally unsurprisingly, still not banned, despite everyone's dishwashers having been rendered useless. Why pay more for fancy pods with unknown-impact chemicals when good, old phosphates do the job perfectly well?

Q: How is this better than a tablespoon of bleach?

Well, it can be run with dishes in the diswasher if you want to. It also has a pleasant, lemony scent. Bleach, especially in such a small concentration, does not do much for hard water build up/lime scale. For that you need something acidic. If you don't want to use these tablets, a cup or two of vinegar (apple cider vinegar smells better, but any vinegar will do) works fairly well. I have also sprinkled baking soda in the grate in the bottom of my dishwasher, then poured the vinegar in and let it sit a few minutes before running the dishwasher to clean it. The reaction of the vinegar and baking soda helps loosen bits of food residue caught in the grates.

Q: Which chemical does it use? Is it citric acid?

It contains citric acid and sodium bisulfate. Does an exceleent job of cleaning. The racks slide in and out so much easier.

Q: My dishwasher has black mold growing in it. What could be causing it. We run the dishwasher typically 3-5 times a week.

Mold is growing because you are running it 3-5 times per week. Put a small amount (half an ounce) of bleach in your dishwasher with every wash and let your dishwasher dry out (leave the door open) after each use. With 3-5 washes per week the mold/mildew will be gone by the end of the week.