Damn… just looks like it didnt adhere that well… it happens… i have 1 very old 450 thats been through the absolute ringer with glue. Its got patches on the inside, outside and giant 1-3” pours of glue encapsulating the old/failed patches inside.
Lets start with ur stand… is the tank unlevel towards that seam in particular? And is it on foam?…
If its on foam, take it out… def, do a level check and add shims as needed even under the acrylic and top of the stand itself. Tank i had keep leaking after several repairs was on foam and an unlevel stand. Uneven pressure over time will find a way to break things.
I havent heard of or used the new low voc 40. Sounds pretty cool tho as the original is most heinous lol…
I guess at this point ill try and get u some pics of my “worst and most desperate repairs” lol… You can put a patch of 1/4”-3/8” thick material and #40 on the outside of the tank running the entire length of the seam. It doesnt look too bad in the end. I have 32”x3”x1/4” strips on the outside fronts of my 450. They kinda go unnoticed.
Only other “crazy” option is to put a piece of 1/4” at a 45 inside the corner. Glue that in 1st then fill the entire void behind it with 40 giving u a ridiculously thick new seam that encapsulates/covers all the old rod/work. I did this twice and it worked. I drilled a hole in the top of the tank to get the glue in the 45d pocket. I used a small hole and it made alot of bubbles squeezing 40 out of a mixing bottle but now that ive done it wrong twice

i could do it again better. It worked tho and keeps ya from having to move/flip the tank if ur alone.
Of course tip and pouring it will also work to cover all that old work. Ive mixed up to a half gallon of 40 at a time and done the same. As for tipping the tank ive used whatever i had around the house. Bricks, chairs, wood, etc… glue sets up in around 40 min and u can move it around just fine until its fully cured after a few days.
Lemme read back here and see what i told ya the 1st time


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