So my only argument is that, if you're saying the substances will alwats react the same, i used the same ammonia to cycle the other three tanks and like i said, theyre crystal clear.
No, just the opposite. My earlier point was that the same "substances" mixed in a different environment can behave very differently. Each aquarium has, or can have, a very distinct and individual chemistry/biology, so adding substance "X" may react differently.
In this present case, from your data it seems you did things a bit differently, another factor. You did no water changes, nitrates got high, then several water changes. I cannot say how any or all of this may have impacted things. And the higher nitrates may be assumed to have been from the cycling, but in fact may have been from this substrate, or a combination. High nitrate tends to run with high organics (one cause, can be others obviously, but organics increasing means nitrates will increase, in my experience).
Okay, let me throw another wrench into the works. My other tank that is currently cycling is now having the same thing happen. Although its only on the glass currently. Completely different substrate in this one.
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Okay change one thing. Additives have been used. I use api tap water conditioner
That would suggest we are back to some biological reaction with the ammonia, tap water organics, ... ??? The API should not be doing this, though again it is one more chemical entering the mix. But I use API Tap Water Conditioner with no problems I have noticed of any sort. One caution though, do not overdose (applies to any conditioner) as you always want to keep chemical and other additives as minimal as necessary, to avoid impacting the system. The API is pretty concentrated, I got myself a measured dropper so I can add drops and make sure it is as little as needed for the water going in.
I dont know if this helps, but these are the plants in the tank with some funky stuff on them.
I see some brush algae on the leaves, but that is not the whitish strands.
If water changes are convenient, by which I mean you are not having to pre-treat your water but can run it directly from the tap, I would do several major changes to get rid of as much of this as possible, and whatever may be in the water column affecting this. Use the API TWC--though I would myself be tempted not to, but just straight tap water. Whenever I do water changes in tanks with no fish, like my QT for new acquisitions when it is fishless, I use straight tap water and do massive changes. I only have chlorine to deal with, I am not sure if I would do this with chloramine as well. Another thought.
/ no. I think you may be looking at something different 
i was looking at the big rocks, not substrate! early morning for me here, brain not working yet
