Without knowing the specifics of your "electro-chemical" apparatus, I can only guess.
Going to a real electro-chemical solution will definately help since the particulate level will be finer. I assume you just desolved table salt in warm water. Remember when your grandma did this when you had a sore throat, it didn't help much then either, but it proved she loved ya...
But before you buy the solution, you will need to know what kind of steel you will be using. There are different solutions for the various steels, some are very specific (works best on ATS-34, etc...), some are very general, like for "high carbon steel" or for "All S.S."
Now the real variables of all of this is your electrical source. Is it AC or DC? What voltage/amperage are you using, and finally, as if the first two were not enough, how long are you applying power?
AC leaves a very shallow (0.001" to 0.005") almost black mark (solution and blade material are the variables here). The AC method is based on the alternating currents, during part of the cycle, metal is removed from the blade, during the second half of the cycle, the metal is put back, but oxidized, hence the dark color...
DC leaves a deeper (0.001" to 0.01") but white to silver color mark. THe DC method means the metal is blasted away from the blade and it collects on the "Wick" Since no metal is redeposited, you are always looking at "virgin" metal.
Now, either way, time and wattage controls the depth and speed of cut.
The more power, the faster, but sloppier the mark. Too low a power setting and all the time in the world will not show a mark if you are moving only one atom a second...
You should strive to create your mark with a time of 2 to 10 seconds. Any less than two seconds and you are probably using too much power, any more than 10 seconds and you are probably using too little power.
I set my Personalizer Plus to AC, 10 watts, for about 8 seconds on my 440C blades.
Hope this helps...
Bruce
