Sudden Melt of established vals?

I have been having issues with BBA over the last 6ish months. I removed a rotting piece of grape wood that believe was the major culprit. I began adding extra Thrive and slowly increasing excel so that they could acclimate.
I think I was very close to finding the right balance until this past weekend. I went on a mini vacation. Left Thursday afternoon and came back Sunday evening. The lights have been on a timer since I‘ve had the tank set up and I had no one try to feed the fish, so basically it should’ve been on cruise control for that short time.
But when I got home last night, the vals were almost completely melted.
Did the fast growing dwarf lily just rob the rest of the plants from any nutrients in the tank in that short of time?

 

Did the fast growing dwarf lily just rob the rest of the plants from any nutrients in the tank in that short of time?

That seems unlikely.

More likely something changed in the plant's environment causing them to melt. Temperature changes can do this (especially if it gets too hot). Do you think the tank may have gotten hot over your mini vacation?

I've read some say that excel can make vals melt. I haven't experienced this myself (and I don't see how this would be related to your mini vacation), but it could be something to consider as well.

 

Liquid carbon and valisneria don’t go, that has caused the melt.

The excel dosing should be minimal with valisneria and it should thrive; Or even no liquid co2 and high flow.

 

That seems unlikely.

More likely something changed in the plant's environment causing them to melt. Temperature changes can do this (especially if it gets too hot). Do you think the tank may have gotten hot over your mini vacation?

I've read some say that excel can make vals melt. I haven't experienced this myself (and I don't see how this would be related to your mini vacation), but it could be something to consider as well.

I don’t think it could be temp related because my home (and tank) thermostat was left unchanged while I was gone, and the tank‘s temperature is what it has always been. This was my first thought as well so it was the first thing I checked.

I know excel is not good for vals. But I’m pretty sure I’ve read that they can be slowly acclimated to it. And I have had pretty good luck over the last few months finding the amount they would tolerate while still having an effect on the algae. But, the amount of excel was actually less while I was gone because I was not adding it while I was away.

 

Looking again at the picture, it looks like your substrate is just standard gravel? Do you have any nutrients below or root tabs? The lack of nutrients in the soil may of causes the plant to die.

 

Looking again at the picture, it looks like your substrate is just standard gravel? Do you have any nutrients below or root tabs? The lack of nutrients in the soil may of causes the plant to die.

I use Eco-complete. This tank has been set up for at least a year and 1/2. The vals have been doing fine. As I said, I had been trying to find a balance with the Excel/Ferts/algae, and for the most part, it was working. This sudden melt down occurred within a matter of 4 days.

Attached is a photo taken just 17 days ago. It looked like this when I left town on Thursday. This is just the last photo I had taken. It is the speed at which these guys melted that has me puzzled.