Increasing phosphate levels

• pH: 6.8
• Temp:
• KH: 5
• GH: 9
• NH4:
• NO2: 10-20
• NO3:
• PO4: 0.5 ppm
• Iron:
• Dosing: 5 mL Flourish, 5 mL iron chelate (0.5 ppm), 40 mL Flourish potassium (~8 ppm), 15 mL KH2PO4 (0.6 ppm)
• NO3:PO4 Cumulative Dosing Ratio: 15:2.4 = 6.25

Notes:
I bit the bullet and ordered a System 1 diatom filter from petsmart.com for $100, since it had free shipping this month (Enter in "PAWDEAL3"). It should arrive next week. I'm still debating whether to soften the water for the next water change by dosing less Equilibrium. I like the harder water in that it seems to help the stargrass stay nice and green (no more black patches). If I soften the water, I could try dosing more potassium separately, but then I would worry about keeping the proper proportion of potassium to Ca/Mg. Having too much potassium in proportion to Ca/Mg may cause a deficiency in Ca/Mg. I may wait and try the diatom filter first before softening the water to see if that has any effect.

Some of the stargrass leaves were showing a little bit of black patches on their leaves, so I added an extra 8 ppm of potassium.

Even though I haven't really tried to maintain the Redfield ratio for a long enough period to judge its success, I decided I wanted to skew the phosphate levels higher, to a target level of approx. 1 ppm, instead of the "ideal" 0.5 ppm for 10 ppm of nitrates. I feel that it is too difficult to rigidly maintain this ratio. I like more the Tom Barr theory that an excess of nitrates/phosphates is okay, won't cause algae, and can suppress other types of algae like green dust and green spot algae. It's more flexible, at least. Currently, there's not too much green spot algae, though there is still some green dust algae growing. It's growing more slowly than last week, though.

I've also upped the CO2 levels a bit from 1.7 bubbles/sec (24 ppm) to 2 b/s in order to try to up the levels a bit to a target of 30 ppm.