NitrAte (NO3-) deficiency !!!
Approximately 3 month after the first plants were added, I experienced something called the nitrAte deficiency. Almost all of my plants started developing yellow leaves with burned-like holes. My mistake was not having the nitrAte test kit!!! The photo above shows the Water sprite (C. Thalictroides) reaction to insufficient NO3-. It starts dying off. The leaves develop blackish color and pieces start falling off. This plant needs lots of nitrogen. It is a fast grower.
Next photo shows the Hygro spp. having yellow lower leaves with black pin holes. The leaves start falling off one by one in a 3 weeks period.
The last photo shows Alternanthera reineckii "roseafolia" lower leaf loosing the color and top of the leaf dying off. These are all signs of nitrogen deficiency.
I started dosing NO3- last week. I found it sold as Salpeter. It is not the recommended KNO3 (potassium nitrate) but NaNO3 (Sodium nitrate). My nitrAte levels went from 0 to 20ppm and my plants are already improving. The water sprite is developing beautiful green leaves and they stay green :-). Hygros are developing new side shots.
One more update; I started adding liquid fertiliser 8 weeks after the plants were added which was a mistake. I should start adding it two weeks after the plants showed that they are thriving.
I upgraded my CO2 system into the DIY Yeast Reactor, and is running since the beginning of May 2006. Now with right NO3- levels and moderate lights and CO2 my plants should see better days.
BTW my Caridina japonica released the eggs and I didn't witness that magnificent moment. The fish consumed it before I could spot them. Now I have 3 more Amanos carrying eggs. I will soon buy a small 28 liter aquarium where I will try to raise the Caridina japonica larvae. Wish me good luck, since it is not easy to breed this shrimp. They need specific salinity for certain number of days which can be very tricky.
Photos by Dusko Bojic.