Changing fertilizer tank

[waj8]

I have been running a planted 120 gallon tank with 2 adult Discus for over a year now without issue. Recently, I added 4 additional adult Discus. I have notice the Nitrates creeping up and have upped my water changes to 40% twice a week. I reduced the KNO3 in my PMDD mix and I am considering cutting it out altogether and replacing it with KCl. The DIscus seem to be providing sufficient Nitrate for the plants without adding it to the tank. What do you guys think about this idea?

I have been reading a thread about adding salt to a Discus tank to help with Nitrite poisoning which is what prompted me to wonder if the KCl might actually be of benefit to the fish. Would the long term effect of the Cl ions be harmful or beneficial?

[Colorado14erGuy]

Hi waj8: I'm new here at Simply and these acronyms are killing me. Could you PLEASE translate:

KNO3 =
PMDD =
KCl =
Cl =

Thanks in advance!!!
Steve

[h2osanity]

kno3 -potassium nitrate
pmdd- poor man's dupla drops (a type of fertilizer regimen)
KCL -potassium chloride
CL-chlorine

All are used when discussing making your own do it yourself fertilizer mixes

[2wheelsx2]

You can also use K2SO4, which dissolves easier than KCl I believe. That's what I do in my cichlid tank (no discus yet). I reduce my KNO3 dosing and maintain the K with K2SO4. Seems to work fairly until I reduced the bioload recently by getting rid of some big fish and my my nitrate is too low so I have to up my KNO3 so it doesn't bottom out between dosings.