My tank size: 122*450*500 Volume about 200L Dolphin C1300 filter Lights: Glo T5 system with 39W Sylvania Grolux Light & 39W Sylvania Marinestar 15000K light. Both have reflectors. plus CO2 I have been using EI as the basis of my daily/weekly dosage program. Currently I mix the following in 2*500ml bottles. AM Phosphorus (Dosage) 60ml Flourish Potassium (Dosage) 25ml Salpeter [KNO3] (Dosage) 6ml PM Florish (Dosage) 40ml Flourish Trace (Dosage) 40ml Flourish Iron Dosage ml According to calculations this is the breakdown of what I am putting into the water. See Column IN Second Column is EI recommondations [info I got from other websites] IN EI Recom Left Phosphate (PO4) 1.377ppm 0.5-2ppm 1.98ppm Potassium (K) 16.644 10-20ppm 29.22pm Calcium (Ca) 0.280 10-30ppm 29.1ppm Magnesium (Mg) 0.220 2-5ppm 8.38ppm Sodium (Na) 0.260 52.58ppm Iron (Fe) 0.890 0.1ppm 0.05ppm Copper (Cu) 0.007 [0.015-0.15] 0.02ppm Manganese (Mn) 0.041 [0.02-0.8] 0.005ppm Zinc (Zn) 0.035 [<0.2ppm) 0.01ppm Boron (B) 0.024 [0.02ppm] 0.00ppm Nitrate (NO3) 18.460 10-20ppm 25ppm After the 5 day dosage and 1 day rest I take a sample to the lab. The results can been seen in the last Column marked "LEFT" My concern is the Calcium and Magnesium. I hardly add any but Lab results state that I have sufficient levels in my tank. Should I add more? All plants are flourishing but my Ludwugia Repens is not having any joy. The leaves are fairly white and growth have came to a complete standstill. Is it the Salpeter? Shoul I go back to Seacham Nitrogen? I am also having trouble with Hair Algea and GSA (Greens Spot Algea) Should I increase Seacham Phosphorus dosage? Lights are 06:15-08:15 & 17:15-22:15 7hours in total I a looking at a cheaper alternative such as Lenolax but did not like the 'other' ingredients. What is your experience with it? It is also known that Seacham Neutral Regulator do increase the PO4 level in the aquarium. I had 1st hand experience. I recon it is a cheaper option than Phosphorus but how safe is it to premix it with my AM EI mix? I hope the experts can help me on this one.