Plant/Fert Questions

[KatieJ]

Got a few plant questions. I noticed over the last week or so, one of my Wisteria leaves seems to be yellowing at the tip, and browning at the very tip. It's shown in one of the pics below. There's also a liiittle bit of browning at the very tip of a couple of other, newer wisteria leaves. Is this a nitrogen deficiency? I only have ~14 red cherry shrimp and two ghost shrimp in the tank at the moment, so they're not producing a whole lot of bioload. I add one or two soaked betta pellets every few days to give them something to munch on other than algae - is this bad?

Also, I'm noticing some browning spots on my anubias nana, also shown in the pics. These are... diatoms, right? *still horrible at ID'ing algae* I'm also noticing a tiny bit of browning at the very tip in one of the leaves at the bottom of the plant.
Edit: The holes in the one anubias leaf are just injuries. I accidentally snagged them on something while planting, oops. :'D

 

[aqua_chem]

Nitrate or phosphate could be responsible. My bets on nitrate though. Whats your levels?

 

[Batt4Christ]

I too would first guess nitrogen deficiency, though a serious iron shortage can also cause yellowing.

 

[KatieJ]

Thanks for the responses. The iron doesn't seem like it would be a problem - I'm dosing Flourish Iron every day, haha

Just checked my nitrates wit the API kit - haven't done a pwc since 3ish days ago. The levels are reading less than 5 ppm, maybe closer to 2 or 3! Ammonia and nitrite are 0....

Would the nitrate levels be too little considering I only have a dozen shrimp in the 5g tank, and no fish? Would I need to consider adding Flourish Nitrogen or something? O_0 I was always a little skeptical on Flourish Nitrogen though because it's just basically adding toxins into the water that's bad for the fish/inverts, right?

(^ This question also kinda applies to the 5g build thread I have, with my post on the planaria/nematodes-looking things on my glass. I thought they really liked nitrates and waste and such. I'm afraid to vigorously clean my Eco-complete because of all the plants that have (finally) taken root there - how else could I get rid of them? There are pics on the thread for identification purposes.)

As far as pH goes, oddly enough, when I tested it it read in-between freaking 8.2 and 8.4. I know as long as it's stable it doesn't matter, but for my plants, shrimp and eventually rasboras, wouldn't this be a liiittle too high? If I went ahead and put my driftwood in the tank, would this lower it?

Edit: Just tested the aquarium water's pH again, and then the dorm's tap water pH. The aquarium results still have the same brownish-purple, while the tap water results, strangely, read a dark yellow color (around 7.4). This is so weird - I know I'm testing this right, using the High Range pH one because the regular pH results just show up as too high for the chart. Any thoughts?