Okay, good and bad news.
Bad news. 1 more out of my original 8 cherry shrimp died.. =( I'm down to 6 now.
I've done 2 water changes this week a 20-30% one and a 50-60% one yesterday and I found the dead body when I got home today. Water parameters seem normal. Ammonia, NO2 and NO3 all zero, pH 7.5. Cause of death unknown.
Day 33 (5/14):
Ammonia - 1 ppm
Nitrate - .3 ppm
Nitrate - 40 ppm
Semi-good news.
I think I've figured out why some plants are not doing so well. I think I've also figured out what has been causing the HUGE drop in pH in the cycling tank. I was trying to figure out how my pH can drop from 7.5 (tap water) to 5(in cycling tank) or below (since the chart only goes to 5) when all I've added was ammonia, Flourish, Excel.
Then it hit me. I've done a few papers this semester on ocean acidification and I think I've figured it out. CO2 mixing with ocean water causes carbonic acid which is slightly acidic. Increase amounts of CO2 in water causes a drop in pH. So far out of the 30+ days, I've only done maybe 3 water changes? I honestly don't even remember but I have been trying to fert at least once a week. I dose smaller amounts of Excel since I've read Vals tend to melt with the large doses of Excel.
I've asked but never got an answer if Excel since it's liquid and not gaseous, stays in the water column longer even with the use of an air pump powered sponge filter. The increase surface movement from the air stone should not be removing excess carbon from the water column, therefore decreasing the pH of my water. At the start of my cycle my tank's water was probably 7.5 which is my tap water. I tested a few days ago and my pH was 5 or below. I did a water change after that to remove some dead plant material and replaced about 25% of the water and my pH increased to about 6.0.
Can a drop in pH slow the growth or melt the plants in the tank? Would excess amounts of Nitrate cause an issue for plants?
Does this mean I should stop dosing Excel altogether because I lowers my pH? Or should I just increase water changes because I've been told I shouldn't during a fishless cycle?
Should I do a mass water change to stablize my pH (to try to save the plants) before I continue my fishless cycle or will a huge mass water change offset my progress with the fishless cycle so far?
Can anyone verify if Excel since it's in liquid form stays in the water column even with excess surface movement which normally releases CO2 out of the water?
Comon with over 1600 views, I'm sure some of you guys can answer the questions I've been asking while logging my cycle process....
EDIT: Upon further thought, I also cut down the 10-12 hours the lights were on to about 5 since I had a huge outbreak in hair algae. The lights being on only for about 5 hours a day might have cut down the productivity of the plants and reduce the amounts of excel, ferts, nutrient intake. That might be associated with the decrease in pH.