Limnophila hippuroides growth

• pH: 6.7
• Temp:
• KH: 5
• GH:
• NH4:
• NO2:
• NO3: 5 before dose
• PO4: 0.35 morning before dose, 0.2 evening after first dose
• Iron:
• Dosing: 5 mL Flourish, 5 mL iron chelate (0.5 ppm), 30 mL KNO3 (7.5 ppm), 5,10 mL KH2PO4 (0.2, 0.4 ppm)
• NO3:PO4 Cumulative Dosing Ratio:7.5:0.6 = 12.5

Notes:
50% water change:
25 mL Amquel+
6 tsp Equilibrium
2.5 tsp baking soda

I originally got 3 stems of Limnophila hippuroides "Gratiola" from a LFS. In the store, the gratiola was a very pretty deep mottled purple with spiky leaves. It requires high light (the store had metal halides), but I liked the look so much that I decided to try it out. I cut the stems in half and planted the 6 stems. Two weeks later, the cut stems are beginning to branch out and the tops have grown 1-2 inches. It's not particularly a fast grower, unlike the Ludwigia "Cuba," which I got at the same time and which has already reached the surface. The new leaves of the gratiola are growing green on top and reddish underneath, instead of the pretty purple. It's probably because the lights are not bright enough.

Back to my favorite topic, algae, I read that algae favors hard water conditions. If the algae doesn't improve much over the next week, for the next water change, I'll probably try to reduce the hardness of the water (usually around 8) down to 5-6 by reducing the dosage of Equilibrium. Before I raised the hardness of the water, the stargrass used to get black patches on its leaves, probably due to insufficient levels of potassium, which Equilibrium also supplies. If I reduce the Equilibrium dose, I might dose some extra potassium separately to compensate.

Over the next week, I'm also going to try to maintain a nitrate/phosphate "Redfield" ratio, which supposedly is an optimum ratio of nitrogen to phosphorus of 16:1 that minimizes growth of green algae and cyanobacteria (blue-green algae). Raise the ratio too much, and encourage the growth of green algae. Lower the ratio too much, and encourage the growth of cyanobacteria. The equivalent nitrate: phosphate ratio is 23:1. Well, I don't know if this works, but it's roughly in the range of what I usually shoot for anyways, so we'll see...