Acrylic vs. Glass

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I agonized over the decision when I ordered my custom tank for quite a while. After weighing the pluses and minuses I went with glass. Plus, the acrylic had huge bracing at the top that would've prevented me from putting pieces in I wanted and limited the type of filtration I wanted to use.

Size, short term and moving big tank = acrylic
Long term durability and clarity = glass

Just couldn't deal with all the special care /tools acrylic would need for cleaning. Even leaning against it for maintenance scratches (zippers, buckles, etc). No one I knew recommended acrylic long term although I still wouldn't mind an acrylic smaller tank (say 100 gallons or less). And even now all the old acrylic tanks I see look like milk or dingy.

Then you have catfish and plecos that can leave sucker scratches, be careful cleaning substrate against the walls, on and on. Not saying it can't be done but I was like, meh.

You're also limited with backgrounds for acrylic unless you velcro fabric on. Acrylic does uv fade over time because of a chemistry change so clarity is lost even if you polish it. The material itself does this and it isn't just reliant on sunlight. You can delay it for awhile but that's it.

Have you owned an acrylic tank? If you don’t mind post a pic of a tank you had that’s yellow, post a pic of an acrylic aquarium you have seen that’s yellow or post a picture of any acrylic aquarium that’s yellow
 
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Why are you limited with backgrounds? As for clarity, acrylic is far clearer than glass. Acrylic distorts less than that of glass as well. Yes it becomes milky if improper cleaners are used.

Acrylic does scratch relatively easy compared to glass. I say relatively for a reason. Many people believe that acrylic scratches like nothing. It still takes a fair bit of effort or lack of care to scratch acrylic. I say this as I had a 6 year old 500 gallon tank without even a scratch by the time I emptied it. Most believed it was still new. I also make custom acrylic tanks so I won’t knock acrylic ;) Unless you clean the tank with sandpaper there is no reason you should be scratching acrylic as badly as people say. A lot of people complain about scratches caused by substrate getting into magfloats. The same thing happens on glass tanks as well. I made a post on this over 2 years ago. The hardness of glass is 5.5. The hardness of most substrates will be 5,6,7. The hardness of acrylic is roughly 3-4. So, using most freshwater substrates, composed dominantly of quartz with hardness 7 will scratch acrylic easier then glass. As you can see though the same substrate can scratch glass. For freshwater use they are very similar. The difference comes in saltwater. Hardness of coral skeleton or aragonite used for reef tanks is 3.5-4. So, when using reef substrates, acrylic will still scratch while glass will not unless there’s impurities within the mix (not purely aragonite). Why this is relevant: a lot of what’s common knowledge in this hobby is taken from reef sites such as reefcentral, reef2reef. There is always a bias.

Painting acrylic is tricky. The clear for life backgrounds are limited to black and two shades of blue. Unless you custom order a color sandwiched on the back.

The clarity thing is overstated / dated. Low iron glass (starfire) is so clear it looks like nothing is there. Biggest problem with glass is the weight when tanks get large, even more so when tall. As a way around some of that I ordered tempered glass all around. 8 times the strength of untempered plus I could go 1/2" instead of 3/4". Added back a few extra gallons of volume too. Tank was still heavy as crap but it did knock off a few pounds.

I'm not knocking acrylic at all, as I said I couldn't decide for the longest. But nobody I knew in the hobby recommended acrylic long term unless it was like 200 gallons plus and even then they were neutral. The background I have on my tank doesn't exist for acrylic tanks.

Yes glass scratches but its harder to do and I don't have to worry about haze from leaning against the tank and causing tiny scratches from zippers, buckles, keys, etc. No one has come up with a polish you can use safely on the inside, either. Water will hide the small scratches but its the ones that build up over time you gotta worry about. And its super critical to not have any deco pieces near or against the wall especially if you have rowdy fish.

Acrylic does insulate better, so there is that. Probably more of a factor in smaller tanks though.
 
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Why are you limited with backgrounds? As for clarity, acrylic is far clearer than glass. Acrylic distorts less than that of glass as well. Yes it becomes milky if improper cleaners are used.

Acrylic does scratch relatively easy compared to glass. I say relatively for a reason. Many people believe that acrylic scratches like nothing. It still takes a fair bit of effort or lack of care to scratch acrylic. I say this as I had a 6 year old 500 gallon tank without even a scratch by the time I emptied it. Most believed it was still new. I also make custom acrylic tanks so I won’t knock acrylic ;) Unless you clean the tank with sandpaper there is no reason you should be scratching acrylic as badly as people say. A lot of people complain about scratches caused by substrate getting into magfloats. The same thing happens on glass tanks as well. I made a post on this over 2 years ago. The hardness of glass is 5.5. The hardness of most substrates will be 5,6,7. The hardness of acrylic is roughly 3-4. So, using most freshwater substrates, composed dominantly of quartz with hardness 7 will scratch acrylic easier then glass. As you can see though the same substrate can scratch glass. For freshwater use they are very similar. The difference comes in saltwater. Hardness of coral skeleton or aragonite used for reef tanks is 3.5-4. So, when using reef substrates, acrylic will still scratch while glass will not unless there’s impurities within the mix (not purely aragonite). Why this is relevant: a lot of what’s common knowledge in this hobby is taken from reef sites such as reefcentral, reef2reef. There is always a bias.
Agree with all of this. I have glass tanks that look like they went through a buzz saw. Nothing can be done at least with acrylic those scratches if need be can be cleaned up. Acrylic is not as fragile as people assume. I take very little "special" care when working in and around it and so far nothing major...this tank is in my kids play area and has been whacked many times. Even cleaning the inside is made to be overly complicated. I use a soft foam pad no issues at all. Dont get me wrong there are scratches caused from my fish rubbing against it while sand is stuck to them but they are only noticeable.

I use novice to clean the outside, do you recommend using something better ?
 
Painting acrylic is tricky. The clear for life backgrounds are limited to black and two shades of blue. Unless you custom order a color sandwiched on the back.
You can paint acrylic the exact same way as you paint glass. You can use a roller, spray paint, air brush, paint brush. You can use spray paint or acrylic paint. The difference is getting the paint off. Glass you can use a razor and scrape it off without worrying about scratches. Acrylic you can not. You can still use a razor, but you will have to buff it afterwards.
The clarity thing is overstated / dated. Low iron glass (starfire) is so clear it looks like nothing is there.
Starfire to acrylic...acrylic is still clearer and does not distort like glass. Glass, starfire or not distorts the view. A lot of people get dizzy looking through glass for long periods of time due to the distortion. Looking into any acrylic tank, it looks like nothing is there as well. Starfire is clear no question, just won’t ever be as clear. Not an outdated fact, still holds true, they just improved glass clarity. Still, there are impurities.
The background I have on my tank doesn't exist for acrylic tanks.
Can you please post a picture of your background so we can see why it does not work? There is no reason that I can think of why it would not work.
 
When i was deciding on glass or acrylic for my tank i had gotten 4 quotes 3 from acrylic tank builder and 1 from a glass builder. The glass tank was actually more expensive than all 3 acrylic quotes. Also got a quote from glass cages but i didnt like their customer service and read a few bad reviews... enough to scare me off

I had 2 glass tanks failed on me. Both were perfectly level. Common denominator was black silicone which was probably just a coincidence but you hardly hear of acrylic tanks failing. Plus acrylic tanks just look to have a cleaner look to them
 
Agree with all of this. I have glass tanks that look like they went through a buzz saw. Nothing can be done at least with acrylic those scratches if need be can be cleaned up. Acrylic is not as fragile as people assume. I take very little "special" care when working in and around it and so far nothing major...this tank is in my kids play area and has been whacked many times. Even cleaning the inside is made to be overly complicated. I use a soft foam pad no issues at all. Dont get me wrong there are scratches caused from my fish rubbing against it while sand is stuck to them but they are only noticeable.

I use novice to clean the outside, do you recommend using something better ?

Novus products with a wet sand prior work very well. I’ve hesdlight polish with success and toothpaste on very minor scratches. A custom blend of baking soda and vinegar in a spray bottle with a micro fibre cloth works for the outside. As for the inside tank comment. Almost all of these products are safe once the tank is rinsed. If you want to leave the tank full of water, multiple company’s have developed underwater buffing compounds safe for fish. Commonly used in public Aquarium’s. If it were me and I was to lazy to drain the tank, I would use wet sand paper and a handheld sanding block.

As for acrylic vs glass benefits:
Acrylic is lighter
Becoming increasingly cheaper (I can build 480 gallon acrylic for less than half a glass equivalent)
Impact resistant
Stronger seams
Easily machinable
No silicone (ugly)
One single piece (molecularly bonded or bonded with a 2 part mixture with minimum tensile strength of 4000PSI)
I think they look “cleaner” or more professional
No distortion
Clear corners
Easy to recognize damage (tough to spot issues with glass tanks until they leak, acrylic you can almost predict failure)
 
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Novus products with a wet sand prior work very well. I’ve hesdlight polish with success and toothpaste on very minor scratches. A custom blend of baking soda and vinegar in a spray bottle with a micro fibre cloth works for the outside. As for the inside tank comment. Almost all of these products are safe once the tank is rinsed. If you want to leave the tank full of water, multiple company’s have developed underwater buffing compounds safe for fish. Commonly used in public Aquarium’s. If it were me and I was to lazy to drain the tank, I would use wet sand paper and a handheld sanding block.

As for acrylic vs glass benefits:
Acrylic is lighter
Becoming increasingly cheaper (I can build 480 gallon acrylic for less than half a glass equivalent)
Impact resistant
Stronger seams
Easily machinable
No silicone (ugly)
One single piece (molecularly bonded or bonded with a 2 part mixture with minimum tensile strength of 4000PSI)
I think they look “cleaner” or more professional
No distortion
Clear corners
Easy to recognize damage (tough to spot issues with glass tanks until they leak, acrylic you can almost predict failure)
I have the novus 123 bottles but only use number 1 with the towelettes that came with it to wipe down the outside every now and then. To remove peanut butter finger prints lol and the like. Never used anything else. How much baking soda vinegar in the solution? White vinegar?

Yeah funny how the clean corners become so prominent after going with acrylic. The silicone on my glass tanks scream at me.
 
When i was deciding on glass or acrylic for my tank i had gotten 4 quotes 3 from acrylic tank builder and 1 from a glass builder. The glass tank was actually more expensive than all 3 acrylic quotes. Also got a quote from glass cages but i didnt like their customer service and read a few bad reviews... enough to scare me off

I had 2 glass tanks failed on me. Both were perfectly level. Common denominator was black silicone which was probably just a coincidence but you hardly hear of acrylic tanks failing. Plus acrylic tanks just look to have a cleaner look to them

Well put. I got a glass tank in my apartment right now. 3 sides starfire 3/4” glass. I was going to do custom acrylic but was limited on size. Wouldn’t be able to get an 8x4 out of the apartment once built on site. So if I made myself an acrylic tank, the eventual sale price would have been less than what I got my setup for. The glass tank I was given was a great deal from a friend of mine so it’s actually an investment tank in a way. I will get back much more then I put into it.
 
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