Still confused...Q? regarding ferts and 2wpg light setup.
I set up my first planted tank and its been 1 month. i just completed my cycle last week. its been moderately planted with myrio, jungle val, combamba, moneywort, hornwort, glosso and some java ferns since the second week. my lighting is 2X 36 watt AHS brightkit 5600 CF bulbs. tank is 42 gallons with 2- 1 liter DIY yeast (good wine yeast) bottles. iv'e learned to swap out bottles and has been holding steady at 14 ppm CO2 for almost two weeks now. my water params that i currently can test (buying more test kits this week) are 0-NH / 0-NO2 / 5mg/l.-NO3 / ph-7.1 / KH-6deg
these parameters have been rock solid and all my plants look healthy and are growing well. the glosso planted in ada amazonia soil started out really well...went through a week and a half of yellowing but recently has really started to recover with green horrizontal carpet growing in nicely. very pleased so far.
iv'e been reading everything i can on planted tanks and spend much time one the forums. what iv'e come to understand so far is basically its a balancing act. depending on what we start out with as far as lighting and co2, and what type of plants we choose to grow (how fast they grow) will determine how much ferts they extract from the water. the goal being supplying them just enough of the right nutrients to sustain their maximum, or near max rate of growth.
a week after i added the bulk of my plants i started adding ADA's liquid fertilizer, stage 1 liquid brighty something or other. the guy at the LFS seems inclined to push ADA products and at the time i didn't know any better. i dont mean to sound like i'm slamming ADA'a products. i'm sure its perfectly fine product but like most of you reading this i love this hobby and enjoy the challenge of micro managing my tank. that being said iv'e since ordered the fert combo pack from Rex Grigg. i'm still waiting for it and also will order phosphate test kit as well this week. (sorry i'm a bit poor atm from this hobby)
So begins my confusion. from everything iv'e read so far it seems the goal is to provide an established amount of any particular fertilizer...for example trying to provide and maintain tank nitrogen somewhere in the range of 20 mg/l. But it seems i am constantly hearing people say that tanks with 2wpg or less really dont need ferts etc...etc.... iv'e been told by well meaning individuals that my tank will require no fertilizer to remain healthy. now this may be true in some respects...for example by just routine feeding i might be providing plenty of phosphates and will never have to add any to keep it in the recomended range....but in others it doesn't seem to make sense. for example my nitrogen doesn't seem to go above or below 5mg/l ever. havn't seen it change yet in three weeks. my question is should i be forcing my nitrogen (or any other lacking fert) to the recomended dose? do lower wpg tanks still need the recomended doses of ferts the only difference being that they will not use them up as quicky due to slower growth as compared to a 4wpg tank? or do lower wpg tanks somehow require less (lower concentration) of fertilizer to thrive.
i know many of you might say dont try and fix what aint broken. i know my plants do look healthy now but that doesn't mean they cant look better or that they might crash and burn from some accumulated effect/neglect?