Glass Tank Outdoors In Winter.. Important

  1. Cold&warm

    Cold&warm Valued Member Member

    Hello everyone!
    Last spring someone gave me a tank he needed to get rid of. It holds 185L/48 gal.
    Due to its size and lack of space I keep it outdoors on an oversized window-sill with no heating or anything else that runs on electricity: there is no way to connect to electrical power.
    It was an ideal summer residence to 1 harlequin, 2 pygmy cories, and 3Everglades pygmy sunfish.
    The winter of 2016-2017 was the coldest one in some 40 years. Generally temperatures rarely go below the freezing point here but this time entire towns in the area remained without water in February due to the frost, water pipes exploded.
    My question(s):
    - Has anyone experience with unheated outdoor tanks?
    - How many days, if any at all, can the surface of the water freeze without damaging the tank?
    - Is adding salt an idea? I have vague high school memories of the lowering of the freezing point when something (salt?) is added to water.
    It would be disastrous if the glass cracked. Due to its size and weight the tank is already difficult to handle when it is whole, I don't want to think of how things would be if it was damaged. It would be difficult to dispose of.
    The coldest it got lately (at night) was about 4C/39F. But with some luck it will not get much colder than that for a few months to come. The water temperature is 7-8C/44-46F.
    Many thanks in advance for any answer!
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  2. david1978

    david1978 Fishlore VIP Member

    Salt will lower the freezing point some but the cories are sensitive to salt so you cant add much.
     
  3. 86 ssinit

    86 ssinit Well Known Member Member

    I don’t think any of those fish will survive the winter. Best to put them in a smaller tank in the house with all the needed equipment and empty that tank and turn it upside down so no rain water gets in it.
     
  4. SaltySeaLion

    SaltySeaLion Valued Member Member

    Cories are sensitive to salt and should be kept in much larger numbers. Harlequins are also schooling fish. Honestly, I wouldn’t leave these fish outside. Maybe some White Cloud Mountain Minnows, but that is really cold water you’re talking about.
     
  5. j

    jpm995 Well Known Member Member

    Tropical fish can't take temps that low. I lost power from Superstorm Sandy and the temps went to 39 degrees. Almost all my fish died. My 240 gal fared best as the water buffered the temperature drop. If the water freezes you will more than likely crack the glass. Even empty you run the risk of the silicon seal shrinking and having leaks at startup.
     
  6. shutterbug13

    shutterbug13 Well Known Member Member

    I have stored tanks outside through the winter but not with water in them. The best option would be to bring the fish inside, drain the tank, and flip it upside-down. If you can't keep the fish in a tank indoors, a large (20+ gallon) food-grade plastic tub with a sponge filter would work really well.
     
  7. OP
    OP
    Cold&warm

    Cold&warm Valued Member Member

    Thanks to all of you!
    I forgot to mention explicitly that all the tropical fish have been indoors for a few months now, from the day that the temperature started dropping fast below 19C/66F. Sorry.
    In the beginning of the summer when it was quite warm during the day I put the Harlequin outside in one of those plastic tubs suggested by shutterbug13. It now houses 1 Paradise fish. The water was over 70F. Next morning the temperature had dropped to about 12C/53F. I still remember the Harlequin: he looked like a fettuccina (broad type of spaghetti) coming out of the water after cooking. To my amazement when he was put in one of the (still) heated tanks indoors he immediately recovered. I did not know they are so hardy. Perhaps because he was bred in Israel, as the owner of the fish store had told me. Possibly he was even bred in the desert where, if I am not mistaken, temperatures differ greatly by day and by night.
    Originally I wanted to get some rainbow shiners for the winter. Here they are expensive and rare; my online seller did not have them in stock. In Hungary they were only a fifth of the price, but they do not ship to Italy. I love North American cold water fish. My Everglades pygmy sunfish came all the way from Germany some 15 miles from the Polish border. Now father and 2 grown-up sons share the 48 gal.
    I renounced at White Cloud Mountain Minnows among other things because they are so prolific.
    In the end I bought Paradise fish, who are said to resist temperatures near the freezing point. I ordered 1 male and 3 females. But the seller sent me 4 males. They turned out to be so aggressive that even a 58 gallon (with a to-the-bone setup) can house ... 1 male.
    Pygmy cories have the charming habit of schooling in mid-water with other fish. Mine live up to their reputation. I only bought those 2 Harlequins because I did not want to disappoint the owner of the shop and back then I had only small tanks. One of them soon died.
    - I will consider the feasibility of turning the tank upside down. The window-sill is narrower than the tank and there is very little room for movement. It may be too great a risk, even if someone helps me. At any rate, I'll empty the tank. .
    - Before being given to me the tank was kept for years in an unheated garage. I have it in a kind of mini/micro porch right behind its glass door. The porch is as deep as the tank is long, plus about 1 foot. I can only hope the silicon will survive the coldest days.
    - Due to another surprise from my online-seller I find myself with another aggressive species: Blue Gularis - I had ordered Aphyosemion bivittatum. There are many fish in the small tank with peaceful fish on the indoor window-sill (1 of 3, the other 2 contain 1 aggressive fish each), but they seem to enjoy each other's company. I hurried to move them out of the 19 gal yesterday, when I noticed that a Blue Gularis had eaten a tankmate. I try to overfilter with 2 Californian-made corner filters and keep an eye on water parameters.
    I have no more room left for anything extra. My friends ask me where I live. Thanks for the suggestion though. Due to low indoor winter temperatures I have a few very powerful heaters. Plastic would be risky, it could melt.
     
  8. A

    Andrew Novice New Member Member

    Do you know the source of Rainbow Shiners in Hungary and if they ship to the U.S.? I'm not having luck here. Thanks/
     
  9. Neutral-Waterinos

    Neutral-Waterinos Valued Member Member

    Hahaha a piece of fettuccina
     
  10. OP
    OP
    Cold&warm

    Cold&warm Valued Member Member

    I have searched but cannot find the email I got from Hungary anymore, sorry. It is very unlikely anyway that they ship to the US if they do not ship to Italy.
    I also asked my Italian fish supplier: he ships only to countries in Europe..:(
     
  11. BReefer97

    BReefer97 Well Known Member Member

    I skimmed through most of this thread and I didn’t see it mentioned that glass shatters when it gets too cold, especially while holding water. So like mentioned above, if you’re not able to bring them indoors over winter, I would go the plastic tub route because it’s not going to shatter due to the cold. You could maybe run an extension cord from somewhere within your house and place a heating mat underneath the tub, preferably with a thermostat attachment.