Aquariums- Acrylic vs. Glass

[DaveS]

Hey guys, would you all mind giving me to breakdown of pros/cons for acrylic vs. glass?

 

I have an 210 acrylic right now and am toying with the idea of changing it to glass. It's got a big overflow in the middle back which I think would be nicer if it was two in the back corners. However by far my biggest problem with the tank is that it's got scratches. There a few pretty big ones on the front pane and it's one of those things which really resonates with my OCD. I work hard to make my tank beautiful and those darn scratches just keep things from being "perfect". Coming a close 2nd to the scratches is that it's a pain to scrape coraline off acrylic without making more... guess what... SCRATCHES!

 

Anyways, I know glass scratches too but I get the impression that it's harder to do. What is the starphire glass? More scratch resistant? Yes I know you can buff out acrylic scratches but for a 210, they might was well be permanent as I'm not likely to break the entire tank down to buff them out.

 

So for me - low maintenance, scratch resistant and pretty are the priorities. Thoughts?

[Carl]

I have a 65 gallon acryllic with occasional scratches that my kids put in. I come home many times to find out that they have taken the Magfloat into the sand, then "cleaned" the acryllic.

 

It's a pain, but I've successfully buffed the scratches out with a kit...and have kept the corals and fish in the tank when doing it.

 

I don't really know if I'm doing anything harm...but so far...no issues.

 

btw...I'm switching my tank out for glass over the next month or so.

-carl

Edited January 17, 2008 by Carl

[fab]

Here is a quick contrast between acrylic and glass aquarium construction.

 

Acrylic:

Light weight, optically clear, not as brittle as glass (easy to drill), soft material (scratches easily), not stiff (bends and bows).

Because the material isn't stiff the bottom must be well supported as tanks get larger

Coralline algae tends to grow more heavily on acrylic, mainly due to the scratches. Scratches provide protective valleys for the tiny buds of new coralline to get a hold on your tank walls and they increase the surface area for the coralline algae to grow.

More expensive: Acrylic material prices depend on petroleum prices.

 

Glass:

Much heavier, thick glass shows 'coca cola bottle' green tint (not optically clear), brittle (more challenging to drill), hard material (difficult to scratch), stiffer.

Stiff: Because the material is stiff, the tank's bottom support requirements for a stand are minimal.

Heavy: My tank weighs 1500 lbs empty. It is a bit of a job to move it around.

Optical purity: Starfire ( a brand) glass is made by a process that eliminates ferrous (iron) content in the glass. This rids the glass of the 'coke bottle' green tint and makes the glass optically clear like acryllic. Material costs about 30% more than regular glass. You will have to judge what thickness of glass produces enough green tint for you to notice. For me the threshold is about 1/4" thick, which means only shallow tanks are not green enough to warrant Starfire glass if the green tint is important. All sides don't have to be made of Starfire glass. You can get them made with whichever sides you want to view through made of Starfire and the other sides and bottom made of regular glass.

Can't drill holes if glass is tempered.

Much less expensive.

Coralline algae will grow on glass, but is a bit easier to keep ahead of because there are no scratches to provide refuge for new (tiny) coralline algae.

 

I absolutely prefer a good starfire glass aquarium for a display tank; using starfire glass on all viewing panels. Support tanks such as sumps, refugia, quarantine/hospital tanks don't have to look good. For these tanks use acryllic for ease of handling if the tanks are large. Use normal glass if support tanks are small ( less than about 75 gallons) for cost savings.

 

fab

[NAGA]

Here is a quick contrast between acrylic and glass aquarium construction.

 

Acrylic:

Light weight, optically clear, not as brittle as glass (easy to drill), soft material (scratches easily), not stiff (bends and bows). it bows and bends if you make it with the bare minimum materials. Glass will do the same but, not to the degree acrylic does though. I can tell you that there are a number of people here on wamas that will say their tanks (acrylic) don't bow at all.

Because the material isn't stiff the bottom must be well supported as tanks get largerglass tanks especially when they are large have to be well supported as well. The bottom of glass tanks also has to be thicker as compared to acrylic which is a cost factor. The support for acrylic is often just a sheet of plywood so the cost of that in factoring projects like this barely need mentioning.

Coralline algae tends to grow more heavily on acrylic, mainly due to the scratches. Scratches provide protective valleys for the tiny buds of new coralline to get a hold on your tank walls and they increase the surface area for the coralline algae to grow.

More expensive: Acrylic material prices depend on petroleum prices. Even with petrolleum price where they are larger glass tanks are more expensive than acrylic ones and if you take into consideration the money it costs to move a large glass tank vs. an acrylic one you will find the acrlic wins that battle

 

 

Strength:

It is widely accepted that acrylic is 16-17 times stronger than glass of the same thickness, with much better impact resistance. Because the joints are chemically bonded, not simply siliconed together, they are also stronger as well, and much more appealing visually. They do not run the risk of blowing out as siliconed joints can. The strength of acrylic tanks give their owners the peace of mind knowing that their tank will not crack, shatter, or blow out unexpectedly.

 

Weight:

Acrylic is roughly half the weight of a glass tank built out of the same thickness materials. This allows for easier moving, installations, less expensive shipping, and will require less persons to get it to where it needs to be. You will not need to lie about the level of difficulty when soliciting help from friends to move your tank.

 

Better viewing properties:

Acrylic of any thickness is clearer than glass due to its natural composition and properties. It does not have a greenish tint and will not ever turn yellow, like the acrylics of yesterday could. Acrylic will not distort like glass will, especially when viewing your tank at an angle. It also has a better light transmission level. You will find few larger public displays that are not done out of acrylic.

 

Better insulating properties:

Acrylic will not conduct heat and cold as well as glass will, thus making it a better insulator by 20%. Acrylic aquariums will regulate and minimize temperature fluctuations better, giving you a more stable system. This characteristic also saves on electricity, as your heater (or chiller) does not need to work as hard.

 

Forming characteristics:

Because acrylic is a thermoplastic it can be formed in almost any way, which makes tank design possibilities almost limitless. Custom curves and bends are much easier to do with acrylic, and sometimes impossible to do with glass. Glass has limitations on size while acrylic does not. For many custom shapes and unique designs, there is no other choice. Spectacular viewing possibilities are available because of the versatility of acrylic. It is also possible for anyone to drill their own acrylic tank while it is often difficult to find somebody to drill a glass tank if you need it done. Acrylic tank joints are also more visually appealing as they are clear and do not require the use of silicone. They may also be rounded over for extra beauty as well as to eliminate sharp edges.

 

Acrylic is refinish able:

The one disadvantage of acrylic is that it scratches easier than glass. However, a wide variety of scratch removal kits are available to the consumer and are relatively easy to use. Scratches in glass are nearly impossible to remove. Scratches in acrylic are easily preventable with proper care and precautions. When cleaning the interior of your tank, do not go all the way down to the gravel line right away. Do the entire tank but leave an inch or two above the gravel line. Do this last. This reduces the chance that you will pick up a bit of gravel on your brush or magnet and scratch the tank. Trying to get too creative with decorations by stacking them up precariously has led to many scratches as well when they are toppled by fish or currents. Scratching is usually the #1 concern of persons considering an acrylic tank, and is easily preventable with proper care.

[/b]

Glass

Much heavier, thick glass shows 'coca cola bottle' green tint (not optically clear), brittle (more challenging to drill), hard material (difficult to scratch), stiffer. BUT WHEN YOU SCRATCH IT YOUR DONE

Stiff: Because the material is stiff, the tank's bottom support requirements for a stand are minimal.NOT TRUE A LARGE GLASS TANK REQUIRES SIGNIFICANT SUPPORT..........FOR THAT MATTER SO DOES ANY LARGE TANK, PLYWOOD OR ANY OTHER MATERIAL

Heavy: My tank weighs 1500 lbs empty. It is a bit of a job to move it around.[/color][/b]AND HOW MUCH DID THAT COST?

Optical purity: Starfire ( a brand) glass is made by a process that eliminates ferrous (iron) content in the glass. This rids the glass of the 'coke bottle' green tint and makes the glass optically clear like acryllic. Material costs about 30% more than regular glass. You will have to judge what thickness of glass produces enough green tint for you to notice. For me the threshold is about 1/4" thick, which means only shallow tanks are not green enough to warrant Starfire glass if the green tint is important. All sides don't have to be made of Starfire glass. You can get them made with whichever sides you want to view through made of Starfire and the other sides and bottom made of regular glass.

Can't drill holes if glass is tempered.

Much less expensive.

Coralline algae will grow on glass, but is a bit easier to keep ahead of because there are no scratches to provide refuge for new (tiny) coralline algae.

 

I absolutely prefer a good starfire glass aquarium for a display tank; using starfire glass on all viewing panels. Support tanks such as sumps, refugia, quarantine/hospital tanks don't have to look good. For these tanks use acryllic for ease of handling if the tanks are large. Use normal glass if support tanks are small ( less than about 75 gallons) for cost savings.

 

fab

 

 

ANY OTHER ACRYLIC DEFENDERS OUT THERE?

Edited January 17, 2008 by NAGA

[six-line]

Yeah .... What Jeff said. I have a 150 acrylic tank that I'm in the process of reconditioning, I was afraid at first that I'd mess it up by sanding it, but let me tell ya it's really easy to get the scratched out and I had so really bad ones!

[flowerseller]

I have a plexi sump online now and just got a 24x24 plexi anemone farm.

I get a 34x33 plexi frag tank very soon. I got plexi tanks after speaking to several "users" after I had heard from so many hearsayers. My plexi sump is lite and a credit card seems to keep it real clean.

I think it all comes down to care.

[SkiCurtis]

Great explanations Jeff. I have both a 75 glass and a 240 acrylic and I like the acrylic allot better .I was also worried about the scratches, but like Jeff said proper cleaning is necessary. I use the red acrylic scraper for the bottom area by the gravel and use my magnet for the rest of it. I do not have any coraline on my viewing area. if you do on any tank then you are not keeping up with your necessary duties. I will always have acrylic for now on.

Curtis

[jnguyen4007]

When I bought my TruVu acrylic tank from TruVu, I also bought a scratch remover kit. The instruction on it said that it is to be used on the outside of the tank only and not on the inside as the chemical is poisonous to fish. If I'm not mistaken, from what I'm hearing from the folks here that it's easy to remove scratches from the inside of the tank. Does that mean that it's safe for me to use the scratch remover kit on the inside of my tank as well as long as it is empty or do you guys have a particular kit that is non toxic?

[extreme_tooth_decay]

Hi folks,

 

I have some experience here as I had an acrylic tank for 10 years. It's now amazing kids at Floris.

 

For me, just the ease of cleaning makes glass a better choice. It took so much longer to scrape coraline with the plastic scraper than it does with a razor blade. I hated that.

 

Also, even though I was very careful, I ended up with a gazillion scratches. And, while it may be possible to polish out, I never did, as most folks wouldn't. Just too much of a pain. Especially for the scratches which are inside.

 

For me, the long-term stuff (cleaning, scratches) greatly favor glass while the 1 time benefits (easier to drill, lighter (ie easier to move)) favor acrylic. Since I'm in it for the long haul, It'll be glass for me from now on.

 

tim

[DaveS]

Hey guys, thanks for the info. I know this is a debate almost as timeless as MAC vs. PC. I was hoping to confine the debate a little bit by providing the parameters which are most important to me. Let me reiterate my criteria so the responses become a little more tailors to what's important- my needs! I understand that in doing this I may not make the "best" choice but given the persistence of this debate, I suspect there is not "best" choice.

 

Ok as I said my priorities are: low maintenance, scratch resistant and pretty. Pretty much in that order.

 

Low maintenance is #1. If it takes too long to maintain, I won't do it and eventually I will probably fall out of this hobby as it just becomes a chore. I have my own business, family and other demands on my time so maintenance has to be low.

 

Scratch resistance is #2. This is not so much as a requirement in itself but as it affects other things. Scratches are ugly, promote coraline growth and make scraping more difficult (see #1). As part of priority #1, I pretty need to use a mag cleaner. It just much easier to spend 30 seconds wiping the front pane with the magnet than going around back (it's an in-wall system), climbing the ladder, climbing onto the tank, getting wet, etc. Also I'm less likely to break corals using the cleaning sticks than the magnet. For the most part I've gotten much more careful with the magnet but I have some old scratches and occasionally get new ones. I've heard you can get the scratches out without breaking down the tank. I'd love to have someone help show me this (NAGA want to come over and show me as well as look at my potential sump mods I'm considering?). If it's not too much trouble, this might remove/lower scratch resistance from the priority list as it means I can get them out when they occur. If it is a pain or I need to break down the tank to do it, then as I said, I'm not likely.

 

Pretty is #3. Well hopefully why this is important makes sense. However that being said, I don't think the difference in how glass and acrylic looks is what I mean here. By pretty I probably mean clean and maintained (see #1).

 

As you can see, cost is not really on my priority list. No I'm not made of money but I see the tank cost as a one time thing. Maintenance, enjoyment and everything else are the real long term issues.

 

Does this change any of the responses?

 

Thanks guys.

[NAGA]

When I bought my TruVu acrylic tank from TruVu, I also bought a scratch remover kit. The instruction on it said that it is to be used on the outside of the tank only and not on the inside as the chemical is poisonous to fish. If I'm not mistaken, from what I'm hearing from the folks here that it's easy to remove scratches from the inside of the tank. Does that mean that it's safe for me to use the scratch remover kit on the inside of my tank as well as long as it is empty or do you guys have a particular kit that is non toxic?

 

The Rainbow lifeguard kit that you can buy for around $25 is a great little kit that is readlily kept around at lfs's. You can use the sandpaper on the inside but, not the creme they provide. Basically all you doing is using your magnet with the sandpaper on the inside of the tank and rubbing out any scratches with the various grits they provide in that kit. On serious scratches however you may need to start out with your standard 600grit and then work into the 1000, 1500, 4000, and 8000 grits they provide.

 

I kept my 750 for 5years and basically every 6 months I'd go through the tank and take out any small scratches that had built up.

[HowardofNOVA]

Thanks Jeff for the Kit info!

Having owned both, I'm hooked on Acrylic for cost, ease of use and appearance.

The ONLY real negative I see with it is the care issue and you can't use a razor blade, but as Jeff mentions an occasional day of elbow grease and appropriate sandpaper will have your tank looking like new in no time!

....ah for me that is coming soon!

 

Jeff,

Can a tank be done with a Starfire viewing panels, then acrylic the rest?

 

Another recommendation: when we where planning the NADC tank, acrylic won out hands down for that project as well!

[zotzer]

Having seen Dave's set up (huge tank, very high placement in-wall, no top access panel from the front), I don't know how he'd ever be able to get to the front, down near the sand bed, with a scraper (without a mask and snorkel....even then, lots of rock and corals in the way).

 

Forgoing installation of a very high front access panel, Dave, I think you already know the answer.................glass.

 

Tracy

[yauger]

Just wanted to chime in my $.002 worth here...

 

Acrylic hands down, I have owned glass for many years and they accrued man many scratches on them without a way to repair... not to mention I hated the fact you just can't move a glass tank without calling a car full of friends to help you move it.

right now I have a 180 built by NAGA and it's as tough as nails, no bowing, no discoloration, and no issues with moving it in position... Asa matter of fact it only took 2 people to lift my 180 without sweating...

[moore030]

I had worried about the possibility of glass breaking, and when I saw my 5 yr. old launch a hotwheel through the window of my living room I decided to go with acrylic for my 240.

 

Another thing is, my tank is the basement where it is usually fairly cool, so the insulating properties of acrylic should help lower the heating cost of the tank.

 

Brett

[Origami]

Hi Dave. You asked for thoughts and have received the endless debate on glass v acrylic. You also said that you already have a 210 with some scratches. Are you set on getting a new tank? Or is it possible to get the scratches out of the existing one without having to break it down (from the stuff that Naga has talked about here)? That would certainly keep you from having to tear your system down and to set it back up again which, it would seem, would be a royal pain (although, as you said, it is a "one time" thing - until you have to do it again, of course). That would, it seems, be the simplest solution if it were acceptable.

 

Otherwise, it would seem that you already have experience with an acrylic 210 and you're not so sure that your maintenance procedures are sufficient from keeping it from being scratched (which seems to be a major issue for you). Glass is certainly harder to scratch but it's also harder to polish out the scratches (and virtually impossible to do well if the scratch is deep - that is, can be felt with a fingernail). And, no matter what, if you get sand in your magnetic cleaner, it's going to scratch - even glass (though they may be micro scratches).

 

So, if you're set on replacing the tank and are unsatisfied with the performance of acrylic insofar as it holds up to your maintenance regimen and expectations in terms of scratch resistance (and don't want to do what Naga does - that is, buff out the scratches about every 6 months), it seems that glass is the way you're leaning despite it's warts (and both solutions, it seems, have warts ). Heavier, yes, but with that starfire glass, it's going to be both tough and "pretty."

[DaveS]

Having seen Dave's set up (huge tank, very high placement in-wall, no top access panel from the front), I don't know how he'd ever be able to get to the front, down near the sand bed, with a scraper (without a mask and snorkel....even then, lots of rock and corals in the way).

 

Forgoing installation of a very high front access panel, Dave, I think you already know the answer.................glass.

 

Tracy

 

Yes, Tracy you make good observations about my dilemma. As an alternative or in addition to replacing the acrylic tank with glass, I'm also considering changing the wall around the front of my tank to create access. I've been examining Bendelat's framing and think I can steal that idea.

 

Here's what I have:

 

 

Maybe doing something like Bendalat did for his tank here:

http://www.wamas.org/forums/index.php?s=&a...ost&p=93336

 

I'm not sure however that I have the space on top to do that...

[zotzer]

Fixing the access issue will open up the possibilities, for sure. May be able to fix up what you've got without breaking down the tank. Although protecting the tank inhabitants during construction will be a challenge and a half!!

 

Oh, and FWIW, Dave inherited this tank with the house, so the design shortcomings are not his doing.

 

Tracy

Edited January 17, 2008 by zotzer

[DaveS]

Oh, and FWIW, Dave inherited this tank with the house, so the design shortcomings are not his doing.

 

Tracy

 

Hah yea! I forgot to mention that. The more I look at what I have, the more I think I'll eventually be replacing everything since they all seem to have shortcomings...lights, sump....

 

The previous owners didn't know anything about the hobby. They just wanted pretty Nemos and paid some people A LOT of money to build and maintain it...

[lanman]

I have a plexi sump online now and just got a 24x24 plexi anemone farm.

I get a 34x33 plexi frag tank very soon. I got plexi tanks after speaking to several "users" after I had heard from so many hearsayers. My plexi sump is lite and a credit card seems to keep it real clean.

I think it all comes down to care.

 

Darnit!!!

 

I was going to patent the credit card idea! Although I find the quality edges on a Wegman's card are superior to most credit cards.

 

I have acrylic for 20 sump, 33 frag tank, and 90-gallon sump.

 

bob

[ctenophore]

My $.02

I've had both glass and acrylic for about 17 years. My second glass tank was an oceanic 110 long, and only managed to accrue two major scratches (visible in water) in the 15 years it has been running. These were made back in the day when it was cool to bleach coral to keep them white in fish-only systems; I was constantly moving large coral heads in and out.

 

My second most recent tank was an acrylic 325, with a 7'x30" front pane. This was a high end sps setup. Coralline grew very fast and it was challenging to keep up with it. It wasn't bad if I wiped it every few days, but if I let it go for a week or two, I could plan on about 3-4 hours of scraping to get it looking new.

 

My latest project is a fiberglass tank with a starfire front pane, inwall. It has the acrylic benefits of being very light, durable, and cheap, plus it has far better insulation than acrylic (foam core walls). I decided on glass after watching my friend in FL clean his 800gal in 15 minutes with a razor magnet. His front pane is 10'x30", or 25 sqft. That's a lot of glass to clean in 15 minutes. If that was acrylic, it would have been a multi hour job at minimum.

 

To me, the biggest drawback to glass is the lesser impact resistance. That's the one thing that I worry about with my new tank. I will hopefully mitigate this somewhat by setting the tank in a recessed frame, about 7" inset from the wall.

 

Good luck

Justin

[DaveS]

Hey guys, not to reopen this debate but something just occurred to me and I wanted to get your input.

 

As we've all identified, cleaning the panes for acrylic is more tedious as you need to use a scraper instead of a mag cleaner to avoid picking up sand and scratching the acrylic. Sooooo, what if it was a bare bottom tank? If there's no sand bed, I would think that allows mag cleaners to not be used without worry about scratches from sand.

 

Am I missing something here? Did I address one of the bigger maintenance issues or did I just replace it with another one? Now if someone could just explain the benefits/drawbacks of a bare bottom tank...

[stevearlen]

This is the primary reason I purchased a 100 gallon Tenecor acrylic tank:

 

"The strength of acrylic tanks give their owners the peace of mind knowing that their tank will not crack, shatter, or blow out unexpectedly."

 

The 100 gallon acrylic is also light enough that I can move it myself. (I had to do that for initial set-up as well as twice when we had a new floor installed in the den (once to move the tank to the utility room and agian to return it after the new floor was installed.)

[MOT]

I have found that if you clean your acrylic tanks more frequently the coraline will not grow on it so easily. Has made a big difference in my tank. Also acrylic is way better for viewing your livestock. It is as though there is nothing between you and the fish. However starphire glass seems to be a pretty good option as well. I have never seen a starphire tank so I am not sold yet. When i had a glass tank I used to wake up in the middle of the night thinking that I had heard dripping... it drove me crazy. That is another nice thing about acrylic. Also acrylic is a great insulator. I think this has all been said but I thought it might help to hear it from a lot of people

[Grav]

Another thing to consider is how you can't get up close to that aquarium. Buffing out a scratch takes a lot of moving a strong magnet back and forth, wich is a lot easier if you can get right up to the tank. With that counter top in the way, you loose a lot of leverage.