There is always going to be some salts buildup, that's just natural. But you want to do what you can to prevent as much as you can. Then if you still get too much build up you may want to use a flushing agent.
I flush the system with every
nutrient change. I dump the spent
nutrients on the plants in the backyard, then I use soap and water to quickly scrub out the reservoir. Then rinse it out real well of coarse. Then I take apart the
pump and scrub it with soap and water, and clean the flexible tubing best as I can before flushing hot water through it.
Once I have the pump and reservoir cleaned and ready to use again, I try to get out as much residual nutrient solution out of the system as I can (tip it up/to the side etc.). Then I begin to flush it out by putting it back together and filling the reservoir about 1/2 way with just water, and running the plain water through the system for about 20 min. Then I dump that do it again. Once I believe I got out all the residual nutrient solution from the system. I then fill the reservoir all the way and let it run through the system for about 30 min, then dump that and do it again.
Once or twice during the grow when I want to do a particularly good flush. Once I have all the residual nutrient solution out of the system. I will add some pH up to the plain water I flush the system with, I raise it to a pH of about 8. The High pH helps to dissolve the mineral salts. Just make sure you bring the pH back to about 6.0 and rinse it through the system before you dump it out and refill with fresh nutrients.
I've used the FloraKleen from general hydroponics (they sent me some for free once), and just don't think it's really any better than just using a high pH. I clean my
grow rocks after the plants are done using white vinegar (just not while the plants are growing) because of the high pH, and that does a better job of cleaning the grow rocks than the FlorsKleen seemed to. I attached some pictures of a test I did once. I picked out some of the grow rocks with the heaviest build up, then soaked one batch in white vinegar, and the other in just plain water that I added some pH up to (to get a real high pH). The results were about the same, so I assume it's the high pH that dissolves it.
I have used the GH flora series nutrients, and liked them quite well. However it got expensive for the amount of nutrient solution I was starting to use. So someone on this forum sent me some of the
Verti-Gro nutrients, and I have had very good luck using them. I have found a few others like these I want to try as well;
Buy Hydroponics - J. R. Peters Inc. Fertilizer Products And Services
QuickGrow Nutrient Fertilizer
P.S.
I would have to check with the manufacture of the nutrients you are using, but I don't think that calculator is intended to give amounts for sprouts (you may want to call or e-mail them). Usually for sprouts I use about 1/4 the nutrient strength, then go to about 1/3 or 1/2 when they become seedlings a a inch or two tall.