So with my 45 gallon tall office aquarium
I'm using PPS-Pro for the first time and I'm beginning to wonder if I'm missing something...
I mixed up the macro and micro components as described (I'm using Green Leaf Aquariums products), made sure I used distilled water, double checked my measurements etc. (I'm a laser physicist my profession, so although I'm no chemist, my measurement techniques are at least decent!). I've been dosing daily since first introducing plants about 4 weeks ago, 4.5ml of macros, 2.2ml of micros. I'm currently doing two ~25% water changes per week and am dosing 9ml of macros and 4.4ml of micros after the water change. But, when I test the tanks nitrates and phosphates, they are consistently reading zero. Nitrates went through the roof (>160ppm) while the tank was cycling, but once the filter kicked in, they dropped top zero in the space of about 3 days (including one ~50% water change).
My understanding is that I'm looking to "limit the water column nutrient levels" (I'm interpreting this to mean peak concentrations) to ~30ppm for nitrates and ~3ppm for phosphates, for a brightly lit tank. I don't have a way to measure PAR, but I have three 24" Finnex 24/7 Planted+ CC lights (running in 24/7 mode). The tank is 28" deep, and its about 25" to the top of the substrate so, just visually, I'd say the light is "bright" but not ridiculously so.
I'm getting a pretty serious growth of brown "hair algae" which I think is actually diatoms, as the strands disintegrate on touch and are only very loosely attached to the plants (and glass). Its easy to syphon it out, but obviously I'd rather get things balanced. I'm guessing the imbalance here is in the nutrients, as obviously the plants aren't going to thrive with (literally) zero nitrates or phosphates!
So, what am I doing wrong? I can't find any advice to suggest I need to dose much higher to get things going, but as the goal is to dose just the nutrients that the plants will metabolize in 24 hours, I'd assume I must have to dose more to get the concentration up to start with?
The plants are doing ok, they are starting to grow, nothing dramatic, but they are growing. The KH is 4dH, GH is 7dH. I have the CO2 running at ~2 bps and limited by a Milwaukee controller to a pH of 6.6, which by my maths gives me a CO2 concentration of 30.1mg/l, which should be just about right (much higher would be toxic to the fish, and I had to add air at night as the fish were gasping at the surface in the mornings).
For completeness, ammonia and nitrites are both zero. Temperature is 78F. Substrate is ADA Aqua Soil Amazonia Ver. 2.
Any advice would be greatly appreciated!