I am relatively new to running CO2 and ferts for a planted tank but here is what I have learned in the last 4 months or so. If I state something wrong I hope I will be corrected by the veterans on this site.
This is from another post on the subforum started by Sewingalot - which I suggest you read as there is some good info in there. BUT, the crux of what I want to say is what Tom Barr and others have stated in that post: Light drives a plant's demand for CO2 which in turn drives a plant's demand for nutrients.
So, if you crank the lights that is telling the plants to grow. If plants have enough CO2 they will then gobble up nutrients. If the don't have enough CO2 they won't take up as many nutrients as they otherwise could, regardless of how how high your light is and how many nutrients you have in the tank (soil or water column).
It seems like you are on the right track. I would keep the current routine for a couple of weeks and see how things settle in. The PPS regimens are pretty lean and you may find that you will need to modify them to suit the needs of your tank. I know I had to up the phosphates in order to combat Green Spot Algae. I also had Green Dust Algae until I cut back on the lights and photoperiod. I can say now that I am pretty free of nuisance algae and the plants are growing pretty well with the modified PPS Pro routine I am using.
Green Algae on glass: If it is Green Dust Algae, try cutting back on light - that worked for me. If it is Green Spot Algae, increase phosphate. The plants are likely gobbling up whatever phosphate you have which allows GSA to appear. I have to keep phosphate levels around 2-3ppm to keep GSA at bay. Note: I am mainly dosing the water column.
As far as proper CO2 levels - some people suggest using as much as possible before your fauna get distressed. Others would say to use less. But this will be driven by your lighting. The more intense lighting and longer photoperiod, the more CO2 you are going to need. Vice versa for lower light tanks. IIRC Rex Grigg recommends shooting for a full 1 point drop in pH from when the CO2 is on to when it is off. So if you don't run your CO2 at night, take a sample in the morning before your CO2 turns on, then take a sample at night right before your CO2 turns off. If you get a 1 point drop you are on the right track. I wouldn't bother using those charts that use water hardness and pH to determine CO2 ppm since that makes assumptions that don't hold up if you have things in your tank such as rocks and driftwood that also have an effect on pH.
I have tried to wrap my head around CO2 and ferts and lights...but for some reason it isn't sinking in. I think it's a combo of school, work, life...anyways, since I can't make heads or tails of all this at the moment...I'm just going to ask. Does my routine seem right or should I change it up?
Pressurized CO2 with DIY reactor - no bubble checker but the color in my drop checker would indicate pH of 6.5
Ferts - PPS Classic with the following:
1.5 Tablespoons of 11% Iron
All mixed with 16oz (ml) of water and I'm dosing 7.5ml of macro every other day, 7.5ml on the other days.
Lights - T5HO 54x2
Plants include a several crypts, Java Fern, Amazon Sword, a Kleiner Baer sword, some moss, a couple anubias, few other various plants...most of them also have root tabs.
No real issues at this point...been doing this for a couple weeks now. There is some growth. The moss is loaded with hair algae, there is brown diatoms on the glass and rocks but that was there before I started this routine, and I just started seeing green algae on the glass. I did have some more lights in addition to the above but I removed those yesterday and I also cut the lights back from 8 hours to 7 hours to see if that helps.
I am open to suggestions and thanks for reading.