Temperature and Glass

Discussion in 'Freshwater Beginners' started by brodylane1122, Jan 8, 2013.

  1. brodylane1122Well Known MemberMember

    Didn't know where to put this, so no worries if it needs to be moved!

    But this weekend it's supposed to get up to the low 50's here in central Indiana, so I thought it would be a good time to take my new (used) tanks outside and fill them up to check for leaks. I will be putting some ice cold water into them from my outside hose.

    My question is will the temp changes (taking the tanks from inside 72 degrees, to outside low 50's, filling with cold water, then bringing them back into 72 degrees when done) be hard on the tanks? I know temperature fluctuations aren't the best on glass, but have no clue as to what extent of change is hard on them.

    I know this may just be overkill on my part, but better safe than sorry, right?
  2. AnthonyC4CWell Known MemberMember

    Well... how big are your tanks, I only ask because I am wondering if it would fit into a large plastic tote. I personally wouldn't want to put a tank through that much of a temp change.

  3. brodylane1122Well Known MemberMember

    two 55's and one 75. So 15 degree changes are a concern for sure? And just for clarification, the tanks will be dry with each temperature change (transfer from inside to out).

    Oh, and the water would be just normal cold water from like inside my house. My basement stays heated, so the pipes aren't ice cold.

    Last edited: Jan 8, 2013
  4. freak78Well Known MemberMember

    Are they newer aquariums? If they are then their probably tempered glass which is physically and thermally stronger than regular glass. So in my opinion 15 degrees I wouldn't worry about it, that's not much of a temp swing.

    Last edited: Jan 8, 2013
  5. Matt BWell Known MemberMember

    I'm also interested in this, I have an empty 65g in my very warm living room and was thinking last night if the cold hose water filling it would cause a problem, I plan to do it today so I'll let you know if it does, it'll definitely be more than 15 degrees difference in my case, I plan to just fill it slowly and let the glass slowly change temp.
  6. freak78Well Known MemberMember

    Think about this. Automotive glass is tempered. So you pull you car out of the Garage and park it in the direct sun on a got summer day. Now that a big temperature swing. Those windows don't break.
  7. Matt BWell Known MemberMember

    Yeah, but if your windshield has ice on it and you throw warm/hot water on it, it may crack.

    It just seems like the water will make it change temps much quicker, causing expansion/contraction at a faster rate than just being exposed to different air temps, I could be wrong.
  8. freak78Well Known MemberMember

    Only if it already has a crack or a defect. The whole process with tempered glass is to make it stronger than regular glass. Going to car washes is winter same deal 20 outside and you power wash your vehicle with warm water. I've never broke a window that way before. But remember this is with aquariums that have tempered glass.
  9. Matt BWell Known MemberMember

    I realize that tempering involves rapidly cooling the glass, resulting in approximately 4x the strength of non-tempered glass, I just wasn't sure if repeating the process on a smaller scale would cause an issue.

    I didn't know it would only crack if a pre-existing defect were there, interesting.

    Good point about the car washes, I never use them so I didn't think about that.
  10. AnthonyC4CWell Known MemberMember

    See...This is my concern... So I will go the long route and explain...

    To start consider the following types of glass used...

    Annealed glass

    Laminated glass

    Toughened glass

    Polycarbonate and other plastics

    Fibreglass with glass front and variations.

    Annealed Glass

    There are 3 types of glass commonly available that are used in aquariums, or more correctly one type that has been processed to produce different qualities.

    Most glass is produced as "annealed" glass. Also known as "plate" glass, "sheet" glass and other local names. When glass is in this state, it breaks into large chunks and slivers with razor sharp edges.

    The first common treatment for annealed glass is to laminate it to another piece of the same thickness.

    While it suffers slightly in the strength department, the advantage of this glass is that if it breaks, no large dangerous chunks are falling about to slash arteries and lop off limbs. It is widely used in doors, low level glazing and anywhere that human impact could be a possibility.

    Toughened glass

    The other common treatment is to take the original 6mm piece and subject it to heat and a fast cooling job. This has the effect of "toughening" Also known as "tempered" glass.

    When this glass breaks, there will be no small, leak, no crack letting out water slowly. When toughened glass breaks, it shatters into millions of pieces and occasionally, it will simply do that without any help from a brick.


    Polycarbonate (or Lexen or Plexiglass or one of the other brand names for polycarbonate)? (Popular in jails and police stations too.) It is easily scratched and is harder to join and seal Fibreglass.

    So I guess the question really is do you REALLY know what your tank is made of?
    Last edited: Jan 8, 2013
  11. oscardudeValued MemberMember

    I wouldn't worry about it. I think it takes a much larger temperature difference to do any harm.
  12. brodylane1122Well Known MemberMember

    Thanks all, I don't think I'll have any issues since I'm putting cold water into a cold tank (I'll let the tank sit out a little bit before I put water in it), and the tank will be dry when it gets moved in and out of the house, so there shouldn't be any issues there.

    I wasn't expecting such a good discussion.
  13. Matt BWell Known MemberMember

    I just filled mine up! Temp outside is 38 f inside 79F (tank is inside) water temp was 30 or so degrees cooler and my tank didn't explode.
  14. brodylane1122Well Known MemberMember

    Now that's taking a chance for the team! Thanks Matt B!
  15. CichlidnutFishlore VIPMember

    The cold water coming out of my tap is about 40 degrees. I just filled my 125 with all cold water, don't want to pay for the water heater to fill that much water :D

    Anyways, tanks didn't explode.

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice