It is truly a pleasant communication with you RedZz. As Steve tended to see the same thing I did so far, I am shocked to hear about the bubble wall. The turtles have been with you for nearly 3 months and the issue arose if I am correct after you placed in the bubble wall (correct me if I am wrong). No issues prior to either turtle. I am only assuming that you installed the bubble wall recently in order for you to ask this question at the present time.
Here is my experience with medications working many many years ago in a exotic vets office that may explain a bit on the situation and it may not as well. Exotic and herp vets will first examine and do diagnosis based on test and observations. Second, if medications are administered in cases, they need to have the estimated age of the reptile and obviously know the species. Here is my thought pattern on the age of reptiles. Dr. Sudo (rest in peace) who was not only my boss but best friend in my personal life as we did everything together in and off the clock, has always determined the age of the reptile for the reason that reptiles UNDER a year old have a weaker immune system and their internal organs have not fully developed yet. Reptiles under a year old coming in sick always received weaker antibiotics then reptiles OVER a year old.
Normally this would not matter in your case but let me point this out a bit. Your turtles are UNDER the year old (being nearly about 3 months old), my curiosity would be and with never hearing about a bubble wall issue, Could it be that due to the sensitivity of your turtles growing internal development stages during the first year, could the turtle of been in the ongoing bubbles to much during the development stage to cause a unexpected neurological issue ? My personally thoughts tell me yes comparing the situation to SBS or what is known as shaken baby syndrome in humans. I am not a exotic vet or reptile vet to determine this and I never seen nor heard about a case such as this ever. It is just a possibility on the internal growth of the turtles organs at this stage of their lives.
I would call a exotic and or herp vet on the matter just to ask if it was me, Not a regular vet though. If it was me, I would remove the bubble jet wall right away as well and hopefully it stops the problem but neurological disorders can hardly be treated if any and hopefully since the turtle is still in developing stages, that it is not permanent . Watch your turtle child over the next week to see if there is any changes (fingers crossed that it returns to normal). Please post a video as soon as you can and another video 7 to 10 days after the bubble wall removal if you will.
Regarding the question on the shell , I agrree fully with Steve on cutting back a bit on the diet. We all have been there and done that and actually one if not both my larger albino red ear sliders will be getting less as well. It is a common area we all have or had somewhere in our lives around turtles.
Cheers Mate.
Not sleeping right now, but he sleeps like this.