PDA

View Full Version : top molding..


WillsNano63
07/02/2017, 08:22 PM
Good Day Everyone!
I recently purchased a second hand 55 gal. aquarium that has no top plastic molding. I've read (with much criticism!) online that this is and isn't really a necessary item. Perhaps on an aquarium that is constructed of thin glass but the one I have has 3/8" thick glass. I understand that without the top moulding, the glass has a tendency to bow out from the outward pressure of the water within. Makes sense however, when I filled my 55 gallon full of water (with about 1 inch to spare) The tanks glass stayed perfectly "flat" with no signs of bowing or leakage for that matter.
The bottom of the aquarium has a thick moulding with a centre cross member for support/strength.
The silicone that is bonding the tank together is very thick in the seems and shows no signs of separating or damage of any kind. Since I've had my (new - to - me) 55 gallon home with me, I have pushed it up a flight of stairs, lifted it up into my bathtub to clean it, and back downstairs where it sits on my kitchen floor awaiting for me to finish building the stand for it.. :spin2:
(something that looks as though I could hold up my house with! lol!)
Anyways, I'm just wondering if the top molding is really necessary or would it have had one in the first place?? Thanks for reading and possibly your reply!

luu78
07/02/2017, 09:32 PM
Hi, assuming you're keeping the tank after all the work you've put into preparing it, you might get gradual stress on front and back glass panels from water movements within tank from wavemakers which can break instantaneously or causes premature silicone adhesion fatique on the vertical seams which can peel off gradually. The easiest and cleanest way is to find a 1/2" plexiglass and run two 3/8" grooves with a hair smaller space in between the grooves than the actual measured distance between both panels and just fit it over the top edges snugly. As water is filled, the panels will bow out ever so slightly and create a strong yet removable brace. You still can achieve the clean rimless look and at the same time, has the support needed to prevent a tank disaster. Good luck

Sent from my LG-D851 using Tapatalk

WillsNano63
07/03/2017, 05:25 AM
Hi, assuming you're keeping the tank after all the work you've put into preparing it, you might get gradual stress on front and back glass panels from water movements within tank from wavemakers which can break instantaneously or causes premature silicone adhesion fatique on the vertical seams which can peel off gradually. The easiest and cleanest way is to find a 1/2" plexiglass and run two 3/8" grooves with a hair smaller space in between the grooves than the actual measured distance between both panels and just fit it over the top edges snugly. As water is filled, the panels will bow out ever so slightly and create a strong yet removable brace. You still can achieve the clean rimless look and at the same time, has the support needed to prevent a tank disaster. Good luck

Sent from my LG-D851 using TapatalkAwesome Idea!! I'm just curious though, with the plexiglass rim around the top; should it not be continuous (360*) including the sides as well as the front and back panels?
- Thus providing continuous support throughout the entire circumference of the tank top? If you have a http// link to this I would GREATLY appreciate it!
Thanks for your reply!!
Will:fish2:

luu78
07/03/2017, 05:52 AM
I cant scientifically give this answer but given the support in the middle of the front and rear panels will greatly brace everything together. As soon as that brace is on, its as if you have two 24" wide tanks. Hehe

Sent from my LG-D851 using Tapatalk

WillsNano63
07/03/2017, 07:03 AM
I cant scientifically give this answer but given the support in the middle of the front and rear panels will greatly brace everything together. As soon as that brace is on, its as if you have two 24" wide tanks. Hehe

Sent from my LG-D851 using TapatalkHmm.. So there is no need for side panel bracing... ok.. I'm still a bit obscured about the designing of the two braces though... Overall dimensions of the strips of plexiglass and the size of and depth of cut in order for them to become supportive. Once I get these pieces on the top of the tank I would prefer to bond them permanently to the aquarium as I see no reason why one would want to remove them even if the tank is empty.
Thanks Again!
Will :fish2:

luu78
07/03/2017, 07:51 AM
My proposal was just 1 piece of plexiglass bracing the center of the front and rear glass panels. Groove it around 1/8" deep with about 1" sticking out of tank edges. So let say the tank width is 12", the cut a piece of 1/2" plexiglass with dimensions as such 14"6". Then groove it at 12" apart and snap it into the edges of tank.

Sent from my LG-D851 using Tapatalk

JZinCO
07/03/2017, 09:14 AM
I get the grove idea and it sounds ideal for strength, but visually unpleasing because of the overhang. What's wrong with a piece a tad <12" and siliconed to place?

luu78
07/03/2017, 09:35 AM
Sorry..just my 2 cents. Function over form I guess.

Sent from my LG-D851 using Tapatalk

WillsNano63
07/03/2017, 02:19 PM
Great reply from yea' all! Thanks and what I have decided to go with was 3 pcs of glass 3/8" thick (thickness of my aquariums glass) x 12.5" long and two inches wide strips of plate glass.
I will fasten these three pieces of glass to the top of the aquarium glass (front to back) and for the middle support I will attach a 2x4" piece of glass under the ends - siliconed to the front and back to support the surface area of the end of the glass support.. This is a bad example of what I am talking about:
L_______J but turned upside down. The letters L & J were the closest letters adjacent to one another to get the basic idea of the centre piece support.
The reason I am supporting the top of the aquarium in this manner is because of the type of filter I'll be using - MarineLand Emperor 400 filter that is too big to fit off the side of the tank.
Thanks again and happy fish keeping! :fish2::fish2: