Need opinions on this acrylic cube

[spikehs]

I heard of this guy off of ebay from the people at RC. I was hoping someone here who has some acrylic experiance could chime in.
http://cgi.ebay.com/16X16X14-RIMLESS-CUBE-NANO-TANK-WITH-CENTER-OVERFLOW_W0QQitemZ190325175464QQcmdZViewItemQQptZL H_DefaultDomain_0?hash=item2c5043b4a8

The tank is 16x16x14 (15.5gallons), Rimless with bent corners. The acylic is 3/8 of an inch. I'm curious if that is thick enough to prevent bowing. From what I've read on acrylic one of the main reasons they get scratch up is because there is bowing when you scrape the tank, leaving two pressure points to cause scratches.

Thanks!

[Myka]

Acrylic was all the rage in the early 2000's because of their light weight and super clear panels. Then we all found out that the lightweight only counts when you move it which doesn't happen often, and the lovely clear panes get all scratched up super easily! I know of a couple people that had sand-sifting fish in their acrylic tanks, and just from them blowing sand around the acrylic got teeny little scratches that gave it a hazy look. It was awful. Glass is once more far more popular than acrylic. I wouldn't buy an acrylic tank.

[sphelps]

It may bow a couple mm but nothing too drastic, it also depends on the quality of acrylic. The cell cast is the hardest so it shouldn't bow at all if that's the case although the price is pretty low for that type of acrylic. There is also continuous cast acrylic which is common for 3/8" thickness and is still good stuff but it's cheaper than cell cast and not quite as strong. Either way it's a great deal, I couldn't purchase the material for much less and if the manufacturer took the time to bend the corners it means they know what they are doing so the seams should be solid.

If you're OK with an acrylic tank and like the size and look of this one I would say go for it. You won't get a better deal and besides the overflow box being a little small it looks really good.

I wouldn't worry about the scratches, nanos are easy to clean carefully and you can always buff them out if you make a mistake. They don't scratch as easily as Myka mentioned, they won't scratch from sand blowing around :rolleyes: unless it's in a sandblaster

[Mrfish55]

I used to swear I would never own another acrylic tank (had a 40 gal one about 20yrs ago, scrached up real easy and looked terrible in about 6 months) and then I just picked up my 750gal monster (used) This tank is 5 years old and has no more scratches than a comparable glass tank the same age, only difference is you can polish a scratch out of acrylic far easier than glass. I think the key to acrylic is to buy a high end tank, there are many grades of acrylic and the saying "You get what you pay for" is certainly true here. Whatever you do make sure it is cell cast and not extruded, extruded is not as strong and is softer making it easier to damage.

[sphelps]

It's not likely extruded because the heat from bending the corners would have caused stress cracks when the solvent was applied. Extruded also isn't much cheaper than continuous cast when it comes to thicknesses of 3/8" or more.

[Mrfish55]

The listing does state it is cell cast but looking at how tight the radius is on the corners I would suspect they are glued up and then machined to give the rounded edge, my old tank was 1/2" bent and the corners were nowhere near as tight as those look. Perhaps an e-mail to the seller could clarify the construction of this cast cube :silly:

[Ryan]

14" deep with 3/8 glass and there will be bowing??? I dont think so.

[spikehs]

domestic cell cast it is. I'll ask him about the construction and see what he says. A few people over at RC have his tanks and are very impressed with them. The price seems reasonable to me.

[mike31154]

I don't own an acrylic tank, but have always been curious about buffing out or removing scratches on them if you do end up making an error. Sounds like a great argument that this can be done, but for the scratches on the inside, near the bottom, who's willing to empty their tank in order to do this? Especially on a very large one. Not a big deal on a nano, or maybe it is. Still stress on the inhabitants and then trying to figure out how to keep the mess to a minimum.

I've also never been a fan of any bow front or bent corner tank, glass or acrylic. Looks kind of pleasing with the round contours, but there's generally a more distorted view through that part of the tank.

[sphelps]

14" deep with 3/8 glass and there will be bowing??? I dont think so.
It's acrylic, pay attention :wink:

[Ron99]

I don't own an acrylic tank, but have always been curious about buffing out or removing scratches on them if you do end up making an error. Sounds like a great argument that this can be done, but for the scratches on the inside, near the bottom, who's willing to empty their tank in order to do this? Especially on a very large one. Not a big deal on a nano, or maybe it is. Still stress on the inhabitants and then trying to figure out how to keep the mess to a minimum.

You cold use the micro mesh polishing cloths. They are basically like sandpaper but on a cloth backing and go to 12,000 grit. They are meant for wet sanding so you could probably use it inside the tank. I doubt the small amount of plastic dust released into the water would harm anything and could probably be mostly removed by filtering and a couple of water changes. I believe they were originally made to polish scratches out of acrylic aircraft windows so they would be perfect for acrylic tanks.

[sphelps]

You can buff out acrylic scratches on the inside without emptying the tank, lost of various kits available and you can attach the buffing pads to magnets to make the process easier.

[Chin_Lee]

JUST MY OPINION but don't try to polish or buff out acrylic when its filled with water. your hand movement will stir up sand or detritus which will get into the cloth and then scratch ur acrylic even more. Personally i hate acrylic because of the scratches and the benefit of having acrylic is only when you move the tank in place or removing the tank. my experience is acrylic scratches very easily but are usually so fine you can't see it but the fine scratches compound to be visible after sometime.

[fkshiu]

I wouldn't worry about the scratches, nanos are easy to clean carefully and you can always buff them out if you make a mistake. They don't scratch as easily as Myka mentioned, they won't scratch from sand blowing around :rolleyes: unless it's in a sandblaster

I would definitely beg to differ in my experience. Acrylic scratches far too easily when you've got a reef even if you are extremely careful because virtually anything - a speck of sand caught in a magfloat, moving a piece of liverock, even a frag that falls - can cause a scratch. While you can buff you scratches, it is a massive PITA after you've done it a few times and it always seems that right after you've buffed out one another one appears. Reefkeeping is high maintenance enough without having to add another job to the mix.

[sphelps]

I would definitely beg to differ in my experience. Acrylic scratches far too easily when you've got a reef even if you are extremely careful because virtually anything - a speck of sand caught in a magfloat, moving a piece of liverock, even a frag that falls - can cause a scratch. While you can buff you scratches, it is a massive PITA after you've done it a few times and it always seems that right after you've buffed out one another one appears. Reefkeeping is high maintenance enough without having to add another job to the mix.
Yes acrylic scratches easily when compared to glass but lets not get carried away. My point was it won't scratch from sand blowing around the tank. A glass tank will also scratch if rocks or corals fall against it or if sand gets stuck in your magnet cleaner. I've owned my fair share of acrylic tanks and have worked with acrylic for years, you simply have to be a little more careful and only use cleaning products made for acrylic.

[Ryan]

It's acrylic, pay attention :wink:

Its 14 inches deep, 16" long and 3/8" thick there might be 13.5" of water in it bust most likely 13" there isnt alot of pressure, that acrylic isnt going to bend.

[Mrfish55]

I think what it will all boil down to is personal preference and how you are with your maintenance, I swore I would never have another acrylic tank yet here I am, VERY happy with mine, I do find it is easier to clean but I am cleaning more frequent, I am only doing a FOWLR and I am not so sure I would use acrylic for a reef as scraping coraline could prove more damaging. I have successfully buffed out a few minor scratches both on the inside and outside. Comparitively speaking I feel this tank at 5 years old looks as good as or better than any glass tank I have had set up for the same amount of time and will only be better as it ages (never have to deal with discolored or peeling silicone in the corners)

[spikehs]

Got a message back from the seller, shipping is an extra $30. So all in all it comes to $190. From what I had investigated previously, it seems like a great deal. I wanted to get a small starphire rimless cube, and I believe the quote I got a while ago was much more (without shipping)

I think i'm going to go for it, I'll let you guys know how it turns out.

[sphelps]

Its 14 inches deep, 16" long and 3/8" thick there might be 13.5" of water in it bust most likely 13" there isnt alot of pressure, that acrylic isnt going to bend.
You're right what do I know about a few mm of deflection

http://i11.photobucket.com/albums/a174/sphelps/acrylictankCellCast.jpg

http://i11.photobucket.com/albums/a174/sphelps/acrylictankContiniousCast.jpg

http://i11.photobucket.com/albums/a174/sphelps/glasstank.jpg

[spikehs]

Cool graphs! How'd you do those up? If i'me reading it correctly the 16x16x14 should (in theory) only deflect 1mm?

Submited an offer to him, so I should have the tank in the next couple of weeks!

EDIT: He just accepted it, whoot. $90 instead of the listed $114, almost takes care of the extra shipping cost to canada

[spikehs]

I'm looking for advice on hole placement if you guys dont mind.

The system is going to be powered by a canister filter to provide all flow (kinda like ninjafish's tank)

I'll have the drain in the bottom of the overflow (as usual) but I'm trying to decide where best to put the return. The way I see it I have two options.

1. On the back, about midway up
2. On the bottom, in the middle, then angle the return a couple of ways to provide some good flow.

Thoughts? I think I'm leaning towards #2, that way we wont see any tubes on the outside of the tank (I'm going to get a second hole drilled in the overflow to provide a dry chamber for the light/heater cords)

Thanks!

[sphelps]

Cool graphs! How'd you do those up? If i'me reading it correctly the 16x16x14 should (in theory) only deflect 1mm?

It's a finite element analysis (FEA), I designed a template which works with the software and does a simple analysis based on basic tank design for whatever size I desire. I can also add bracing and various other features if needed. Front to back or side to side you may see up to two mm total but it bows out less at the top so it'll probably be close to about 1mm total. Basically you won't really notice it. You may notice a little difficulty in macro photography in the red area but that's it.

I'd vote for option #2, you can build a center structure of rock to cover the return outputs.