I own over 3,500 plastic discs -- C.D.s, D.V.D.s, Blu-ray Discs, and 4K U.H.D. Discs. I have only experienced "disc rot" on one occasion. My copy of Napoleon Dynamite on Blu-ray turned a dark bronze color and refused to play. I replaced it and looked at several hundred discs at random. "Disc rot" doesn't worry me. I'm 40 years old and believe that every day is a gift. We will die and decompose and everything will fall apart as well. We live in a universe of entropy....

*Listening to the first CD I ever bought in 1989. Plays perfectly! 🧐

My oldest CD is from 1991. It plays perfectly fine.

I bought on Thrift Store a Factory sealed 1997 Snapcase I opened and inside came with a paper inside telling consumers how to properly protect the disc BATMAN 1989 film double sided fullscreen and Widescreen. I opened and watched it. No glitches, no skipping. No freeze up. No disc rot. Film both side plays perfectly. Not bad for a 26 year old disc.

If my assumptions are correct from your description, that milkiness you are seeing on your Fortress disk is a manufacturing problem. It is where the plastic layers weren't sealed correctly at the factory. Rapid temperature fluctuations causing the expansion and contraction of the plastic, allows moisture to seep in and causes the reaction you are seeing. Because typically it is not physical damage to the aluminium structure (like disco rot/oxidisation) it should continue to play fine... until it doesn't. In Japan they are heat treating the discs and compressing them to extract the moisture. This is usually for high value data discs with a gold reflective layer. [I work in digital compositing and digital art for the film industry.]

I run a small dehumidifier in my movie room during the summer months to control moisture.

Blu-rays are already close to 20 years old (20th birthday will be mid-2026). I've never had issues with them, even my old ones, so we already know they are going to last well beyond that 20 year estimate.

A very interesting topic and a matter of concern as my collection has grown over the years.

Polycarbonate is a seriously tough material … hence used for aircraft cockpit canopies and laminated into the construction of bulletproof glass. However, it will degrade under prolonged exposure to UV radiation (sunlight). This will cause it to lose transparency and to become brittle. This is most commonly experienced with car headlight fairings as they become milky over time … but you’ll also see it if you look at old aircraft canopies that have been left to rot parked outside or dumped in boneyards.

Thing to remember is that ALL polymers are hydroscopic to some degree … ie they will absorb water directly from the atmosphere. Aluminium and water = the white fungus you see on unprotected exposed ally surfaces.

The weakness in any laminated construction formed by a layer of adhesive … is the interface of each contact surface. So, as the data layer comprises one such contact surface in the construction, any moisture that can get to that layer will eventually result in the aluminium degrading by corrosion. There are really only 2 ways water can get into the layer, one is by absorption penetration of the polycarbonate discs, the other is by edge penetration of the adhesive layer.
Edge penetration could occur from choice of the adhesive material (if it were more hydroscopic than the polycarbonate) or by poor adhesive bond quality providing for moisture absorption by wicking.

Bending of the discs will encourage delamination at the adhesive interface, and this weakness will get worse with age, but I wonder if the delamination experienced in cases of laser-rot is actually a result of the corrosion of the aluminium layer … as the aluminium corrodes, the layer will expand and lever the 2 polycarbonate layers apart.

My comments are based on 40 odd years in aerospace, many of which were associated with components manufactured of various composit materials and constructions, including highly stressed structural elements.

Either way, as described in your video, the best key to long life will be to treat the discs with care and protect them from sunlight and moisture … to avoid damaging the protective surfaces which may make it easier for moisture to penetrate the polycarbonate … and to avoid causing any unnecessary flexing or bending of the disc which will put undue strain on the inner layers holding the disc together.

I am not personally aware of any failure of my DVDs or Blu-Rays … but I have had problems with Laserdiscs … the worst was Eraser, which I recall manifested symptoms within just a few months of purchase. Unfortunately, as I had bought it on a visit to the USA, it was not very practical to return it to the store 😢.

The main difference between a home made DVD / BR agains a retail one is that the retail discs are stamped and not burned, therefore the information on the disc is laying deeper and will less suffer from scratches, dust, finger prints etc.
There was a time in de 80's when cd's were made bad using bad materials wich resulted in losing parts of the upper layer of the disc, the coating just fell of in pieces, I never ever had one problem with that on DVD or BR.

I have experienced disc rot on one occasion, and I have owned 3,000 discs. The disc that rotted was Napoleon Dynamite (on Blu-ray).

I've used a different method to store my disks for practical reasons. I have over 9,000 disks and need space to store them. So I toss all the cases they came in. I don't use sleeves or binders either. I put them in Atlantic 80 Disk Storage Manager.  Each hard plastic cylinder holds 80 disks and they take up a lot less space than the original cases. Fingers crossed.

My only experience with Disc Rot is some of the used DVD’s and Blu Rays I purchased off EBay had some of the brown ring around it. It was rare, but I’m fairly sure I’ve only seen like, 5 out of hundreds.

I have quite a few bluray's that are already almost 20 years old, and those are the ones with copper coloring on them and they play just fine.

I have always heard disc rot was more an issue with laserdiscs and it had to do with the adhesives holding the two sides together. I got into buying DVDs when they came out in 1997-98 and haven't had issues with disc rot. I think a big issue is with packaging and the way you sometimes bend the disc to get out of cases which can cause that separation of laters.

I’ve had my movies in binder books for over 20 years and have never had an issue.

Most of my blue rays are over 10 years old and they still play fine. I have DVD's  that are nearly 20 and they still look and play fine. I also have a Journey best hits CD from 1997, and it still plays and sounds good.

Agreed, no issues with DVDs or CDs from the 90s as long as they are taken care of, as far as my collection goes. And I have media from Salvation Army, Goodwill, eBay, garage sales & Marketplace, with no rot to speak of.

Most of the issues are just hype to get people to buy more stuff rather than real issues that need to be addressed.

I store my discs many of them on folders for many years no issues but have had issues with disc rot in cases which was very strange love the video

HD-DVD and Warner Bros ... a nightmare. I had about 40 Warner HD-DVDs and not one is not at least a bit rotten. Besides this I haven't ever had Disc-Rot (Laser-Rot) on CD/DVD/BR. Just sometimes on Laserdiscs. My oldest CDs are from 1985 and oldest DVDs are from 1998. Not a big issue until now.

Taking care is not always the way to prevent Disc Rot. The main issue is oxidation off the allow layer, most of the time caused by bad glue. Scratches are not important, even light does not harm the data rapidly. But a bad pressed disc is a curse (like the HD-DVD Warner media).

I have been collecting for at least 20 years, and I have never had any problems with disc rot. I have always taken great care of my media collection