Acrylic?

[Kharn]

G'day all

I was wondering if anyone here has had some Experience with Acrylic Tanks? I am wondering this because the tank I had plan to build from Glass may just be too heavy to move. The general dimensions on the tank are around 60x30x30 (inch) 230ish gals, is there anything restricting me from making this size of tank out of Acrylic? Is there any bracers that would be needed for the centre? Would the tickness of the Acrylic eliminate the need for a brace?

I recently found out that my "God Mother" works in a large Acrylic business, generally working on government and large Franchise projects. An Acrlyic tank WOULD be lighter, but would there need to be any additional support for it (I plan on going very thick Acrylic to eliminate the need for supports IF, and only IF the extra thick walls will help)?

EDIT: I have read in multiple forums on here about people using arcylic CYLINDER tanks, however I do not think I have come across anyone with an Acrylic tank that is Rectangular and of this size...

 

[DWhatley]

I have done a little reading no acrylic tanks as we considered building one (and did not) and can point you to some of the considerations without being able to provide proper calculations. Note that all my primary (140, 50, 45, 35, 29, 15) and most of my smaller aquariums are acrylic with only the Nano, feeder and sumps being (low grade) glass but all are store bought not DIY constructed.

1. Without top bracing, they will bow. Our hex tanks Bow far less (if at all) than our rectangular ones so there may be a researchable parameter for flat sides vs pressure. Most acrylic tanks have a full top with cutouts. Two of mine are open (one has just become a sump) with just a center support bar and they definitely bow.

2. Unlike glass, an acrylic tank will need full bottom support.

3. They scratch, easily (how easily depends a lot on the acrylic). The problem being on the inside. The outsides of our have not been a problem. Unlike glass, scratches can be buffed out but it is a major undertaking to make it look like new and requires a lot of time and elbow grease - not a one day project. One member does buff his up using an algae magnet. My buffing success has had very mixed results.

4. They clean more easily but note #3 above. You are limited to very soft scrubbing so stubborn algae is a problem.

5. It is said that they yellow if they are not made of Cell Cast acrylic. I have several older acrylic tanks and they do not scratch nearly as easily as the newer Cell Cast ones and have not yellowed.

6. Photography is more difficult both because of the scratches and because of the acrylic.

7. The seams are welded by melting the joining angles with a special cement and the edge cut is critical. Acrylics don't pop seams over time like siliconed glass but getting a proper initial, leak proof fit is not for the faint of heart. I would suggest constructing a sump or fuge first. If you fail to have the proper knack, it can be patched and still used but will help you decide before investing in a potential disaster.

7. Besides being lighter, acrylics are far easier to modify, drill and customize as well as patch if something does not go quite right (other than the seams) or you want to change the orientation over time. The patching is not pretty but it will hold water.

8. You can mix clear and colored acrylics to create an opaque back, reducing your cleaning requirements along the back and/or sides.

I hope this give you some ideas for doing more research. There are some DIY threads and direction on the net if you start to get serious in the undertaking.

 

[Kharn]

G'day

The level of information there is great however, I still need to talk to my "God Mother" to see if she can supply me the Acrylic.

Cheers

 

[Joe-Ceph]

There is one other difference between glass and acrylic that might be important, and that is that acrylic is a much better thermal insulator than glass. My glass tank (for a bimac) is kept cold (60 to 65 degrees F), and on humid days I can get water condensation on the outside. That wouldn't happen as easiily with an acrylic tank, and would never happen with a thick acrylic tank (> 3/4"). If your pumps produce a lot of heat, an acrylic tank will retain more of that extra heat, which is good if the tank is in a cold basement, but bad if the room temperature is normal, or high. An acrylic tank might require a chiller where the same system with a glass tank would not.

 

[DWhatley]

There is one other difference between glass and acrylic that might be important, and that is that acrylic is a much better thermal insulator than glass. My glass tank (for a bimac) is kept cold (60 to 65 degrees F), and on humid days I can get water condensation on the outside. That wouldn't happen as easiily with an acrylic tank, and would never happen with a thick acrylic tank (> 3/4"). If your pumps produce a lot of heat, an acrylic tank will retain more of that extra heat, which is good if the tank is in a cold basement, but bad if the room temperature is normal, or high. An acrylic tank might require a chiller where the same system with a glass tank would not.

I didn't think about the heat issue with my new set up as it is the first time I have use acrylic for a sump (my other sumps are glass and contain all the heat producing motors but this time I used my old tank for the sump). Fortunately, it is open topped but I will monitor it more closely now.