Originally Posted by Jill90
By two of these I meant two fixtures. So I have two bulbs in each equaling four bulbs all together. And I'm adding the Flourish liquid comprehensive each week. I think its around 1.2ml each week since the bottle says 5ml for every 60 gallons. The root tabs were Seachem Flourish Tabs
OK. My thoughts are that there is first of all too much light. Now, before we go further, this would normally first show up as increasing algae, since the plants will stop photosynthesis when something runs out, and with excess light this limiting factor is likely to be CO2. But you haven't mentioned algae... so I'll move along.
Anubias is a shade plant, and yellowing usually if not always means the light is too intense. I would remove one of the fixtures. With NO [thanks Quantum] two tubes is more than enough over a natural setup; I only have one T8 tube over my 33g. An 8=hour day is fine, or should be.
With Eco-Complete, once a week dose with Flourish Comp should be sufficient. As you do have the light, maybe dose it twice. Same amount (for your 36g, 1/2 teaspoon each dose, twice a week). I would remove the substrate tabs. With an enriched substrate these are not necessary. I have Flourite substrate in one tank, it is much the same as EC, and I use Flourish Comp once a week. But I have less light intensity.
Don't vacuum the substrate, the waste organics provide most of the CO2 as it is broken down by bacteria.
A photo if you can of the entire tank would help, in case there is something I'm not catching and might see. I'm wondering just what the dying leaves look like; are there brown blotches that spread, or yellowing from the edges?