How do I fix the issue with white film on utensils in dishwashers? Is it okay to use dishwashers if water hardness is 900 ppm? I've purchased a Dishwasher from Bosch (SMS60L18IN). We were very satisfied with it's first wash when it gave us clean utensils without any problems. We put a 3 in 1 tablet then. Now, I use a special salt, detergent and Rinse aid... all from Finish.

From the 2nd wash onwards, it started giving white film on almost all utensils and food residues are not cleaned on some.

I tried all workarounds that I found online like changing detergent amounts and using the venegar trick.

The issue I was thinking and the company engineers suspecting is the water hardness which is around 900 (or 920) ppm. They changed the hardness level in the machine of to H7 (this is the max one for 8.9mmol/L hardness that the company specified) suggested me to run the machine for a few cycles to get rid of water residue from previous cycles.

I've already ran four cycles and the issue still persists. Is the water hardness the cause alone? Would be there other issues like the detergent or salt?

Following are the things that I observed:


The first wash was perfect. We haven't used sale here. Second and
third washes are a bit okay. 
In the second wash. We put a 1.5 kg of specially recommended salt (it's brand is Finish) 
Issue worsened from the fourth wash. 
I realized that I haven't filled the salt resorvoir with water (the company recommends to fill it with water when you use the machine for the first time) and then filled it with a glass of water.
The company technicians said that is not a big issue as the machine will itself dilute the salt with water after 2 or 3 washes. 
I ran the machine by pouring a cup of vinegar as suggested in some articles and I found that the white layer on the machines door was gone and utensils in the next wash are somewhat clean. Also, I tried changing detergent amounts, rinse raid quantity settings and switching hardness levels with each wash.
Tried changing the size of the load with each wash
Even if we purchase a budget softener like this, it may have low output rates and that gives new problems.
And an important thing is that we believe it's too noisy (it gives knocking sounds while rinsing) like a cloth washing machine. The company staff said it is normal or I guess it is not that loud when they are around:)


More details


Name of the detergent, salt and rinse-aid's brand is Finish 
Am I still using all-in-one tables? No


The company staff recommended water softeners (of a different brand as they don't sell softeners). But I fear if it brings new issues like the change in flow rate (individual tap softeners have low flow rate, i.e., 2 litres per minute where as the dishwasher requires 6 litres per minutre). Ours is a rented house so I can't install a permanent or full house water softener.

Could anybody tell me if you find any other issues here other than the water hardness? Any suggestions or solutions are welcome.
Most likely the problem is your water hardness. A few years ago, they removed phosphates from dishwater detergents. Since then, white films from calcium salts are a problem on glassware. Finish detergent (the little blocks with a red button) is excellent.

Try using white vinegar (or even CLR) to get rid of the film for a cycle or by hand. Use Finish detergent. Add some TSP (trisodium phosphate) with every load, which you can buy at a home improvement or paint store, and also use a rinse surfactant. Cross your fingers.