I'm fairly new to planted tanks. I've run a few nano tanks with buce, hairgrass, babytears, monticarlo, dwarf babytears, pearlwead, ammannia gracillis, staurogyne repens, hydrocotyle tripartita, dwarf chain sword, and java moss with fairly easy success. I don't use Co2 and I use fairly simple medium lighting. I've also run an anubias, java fern 55 gallon. With a Current USA orbit light set at 100% green, 75% red, 50%white, 25% blue on for 10 hours, I use the full line on ADA Ferts on them, even though I'm getting new growth, I'm also having die off for lack of Nitrates. I can't seem to get them above 5ppm. This is also a Discus tank so, yeah. Also I can't seem to get the ph below 7.8 in this tank. I change 5 gallons every 3 days with 7.0 water. I use eco complete substrate so the rise of ph makes no sense to me. Ammonia, nitrites at zero. Nitrates can't seem to break 5ppm. That useless rant to give you an idea of my lack of experience and to ask - I'm going to set up a red stem grow out tank. 20 gallon long with a Fluval planted 3.0 and UNS contosoil. How many bunches would I be able to fit into that tank?