Should I add ferts to my low tech 30g?
Because of work, life, and my 4 other tanks (which I recently tore all of them down), this 30 gallon has been a bit neglected. Now that my other tanks are gone, I'm going to refocus on this low tech setup and try to get things right.
my 30 gallon is:
Miracle grow organic mixed with laterite, capped with pool filter sand
2x21 watts of t5no light. One bulb is slightly red/pink, the other is 6700k.
Amazon swords lining 3/4 of the background
Dwarf sag and some kind of mystery crypt (red/brown squiggly short leaves) in the foreground.
Since I've rescaped so much over the past year, I've probably lost like half of my dirt substrate. So large sections of my substrate are probably 80% sand.
My tank certainly looks nice, but the plants most likely are having some kind of deficiency (couple of holes in the sword leaves that you can only see up close, and slow growing / slightly yellowed dwarf sag).
What I really want is a carpet of dwarf sag (or at least a faster growing dwarf sag) and I want my amazon swords to produce runners so that I can finish planting the background without going out and buying new amazon swords (I really just want to avoid getting a slightly different species that may or may not clash or grow differently than the swords I already have.
So I've been wondering if fert dosing is the way to go. I know about dry ferts and EI dosing and all that, but I really just want to know how effective buying a comprehensive fert (like flourish) will work in my situation and whether or not dosing liquid carbon (flourish excel) will significantly help as well.
Also, if I were to dose ferts, is my low light going to bottleneck the rest of my system and cause problems? Since I had so many other tanks, I still have tons of equipment I can use (such as lights) if I need to add them.
Thanks for any input or advice!