How Much Of A Temperature Fluctuation Is Normal? Question

Discussion in 'Heaters' started by Sokonomi, Apr 16, 2019.

  1. SokonomiValued MemberMember

    Hi everyone,

    I'm quite new to this whole aquarium thing, and i'm not sure if im doing things right.
    It seems with my current setup the temperature drops a whole degree celsius at night,
    going from 24.1'c at noon to about 23.1'c when I wake up.

    Most of the fish I intend to keep will be comfortable in the range of 21 to 26,
    but i'm not sure if that means they are ok with the temps fluctuating daily.
    How much can fish comfortably tolerate?

    For reference, my tank is a standard juwel primo 70L with a 50w heater built into the filter.
  2. DoubleDutchFishlore LegendMember

    Hey fellow countryman,

    Not any problem for the fish. I'd say it is even better (most of my tanks are unheated)

    It is strange though the heather doesn't keep the temp steady / doesn't seem to cope.

    Greetings Aad

  3. SokonomiValued MemberMember

    I guess as long as they stay within min~max parameters they should be alright.
    Water gets colder at night in the wild, too, I think.

    I was just wondering if a 'pewny' 50w heater can manage a 70L tank.
    Its in my bedroom so it ll never have to deal with actual winter temps,
    but night time hitting 17'c is not unheard of for my home.
    It will have to manage heating 70L for +7'c.

  4. DoubleDutchFishlore LegendMember

    Mmmmm info tells 50W heathers can decently heath uptill 50 litres.
    Still think it is strange it drops. It should start heathing and keep it up if surroundings might dropp to 17C.
    Is there a decent waterflow in the filtercompartment where it is in?

    My unheated tanks drop to 17C in winter.
    Depending on fishspecies that isn't an issue. My cories, oto's don't.mind.

    Last edited by a moderator: Apr 16, 2019
  5. SokonomiValued MemberMember

    The filter is only 300L/h, so there isnt an awful lot of it, but this is necessary for the low flow fish I want.
    It is admittedly a bit of a 'basic’ filter that's just foam;

    I might buy something better with media in the future, when I figure out what I should buy. :joyful:
    For now though, ill have to make due with this, if the heater allows for it, atleast..

    I just find it strange that Juwel includes a 50w while just about every guide tells you 100w is needed.
    Does Juwel just expect you to keep the tank in a 24'c room or something?

    My fish selection is mostly asian, kuhlii loaches, celestial pearl danios, harlequin rasboras, that sort of thing.
    These all tend to like it a little warmer, so im not sure if its gonna be enough for these guys.

    I currently have it dialed so it hits 24.1'c in a 20'c room, and it does so during the day,
    but at night it dips and it doesn't seem to catch it well enough.
    I could run it a little hotter during the day so it wont dip too low at night?
    Last edited by a moderator: Apr 16, 2019
  6. DoubleDutchFishlore LegendMember

    I wouldn't. Only thing I am worried about it will be "on" at night constantly.
    Is it possible to get it out and place it in the tank itself temporarily to look what happens then (maybe it can get rid of its heath in the compartiment making it to turn of when the water in there is heathed to the right temp).

    Cruel uhhhhhh Juwel is champion to sell stuff that should be replaced quite fast.
  7. SokonomiValued MemberMember

    I could try moving the heater outside to see if that stabilizes things, but that's certainly not a long term solution. :')
    Summer is coming, so ill have plenty of time to solve this (I do have an AC, luckily), but i'm not sure what to do,
    other than just throwing a heap of money at it to replace the whole thing.

    I already had plans to replace the juwel filter/heater (50w heater and a foam-only filter is really bare minimum).
    No clue on filter yet, but I had my eye on a   because its small and unobtrusive,
    though im wondering if I'd be trading in one donkey for another because its compact..
    I also hope the LED isnt super loud.
  8. DoubleDutchFishlore LegendMember

    Think the link to the filter shown was removed.
  9. SokonomiValued MemberMember

    Not sure what you mean by that?
    I didn't link a filter, just posted a picture of juwels bioflow one.
  10. DoubleDutchFishlore LegendMember

    Ahhh okay thought you did after the sentence

    "No clue on filter yet, but I had my eye on a"
  11. SokonomiValued MemberMember

    Oh theres a link there, its missing for you?
    It should link to a dennerle 100w thermo compact heater.
  12. DoubleDutchFishlore LegendMember

    Ok Dennerle is a good brand to me. I use Eheim Jäger and a Fluval E (digital).
    Think you hardly can go wrong there. Filter is a different thing.
  13. SokonomiValued MemberMember

    Dennerle is usually reasonably priced and very aesthetically oriented,
    thats why I liked their heater, its flat and matte black and would camouflage well on my chalkboard black background.
    Its not the conventional glass tube, so I wonder how well this newfangled flat plastic thing would fare compared to those.

    I've seen the fluval stuff, really nice, but a bit rare in our country it seems.
    Their U2 filter has a ton of media room and probably isnt that much bigger than this dinky Juwel one.
  14. DoubleDutchFishlore LegendMember

    Hornbach and Zooplus have them (Hagen Fluval). Check now and then. Often cheaper ! (but free posting from a bigger amount).
  15. SokonomiValued MemberMember

    Thanks for the tip, Dutch prices are a joke half the time.
    I asked around for a seachem Tidal 55, all of em wanted +80 euros,
    but I can order it on for 45, free shipping..

    This morning my tank was 24'c again, so no nightly temp drop at all.
    I'm starting to suspect this JBL thermometer to be a bit flaky... :rolleyes:
  16. H2O ConciergeValued MemberMember

    Could sunlight be causing the fluctuation of temp? A 50 watt may be a bit small for your tank, 75w may be better. On my bigger tanks I have multiple heaters and use a controller to monitor temp and turn them on/off. This way I bypass the thermostats of the heaters themselves which can avoid many problems. I've had a Tidal 110 as a backup on my 46g (174liters) and been very pleased with it.
    Heater controller.jpg
  17. SokonomiValued MemberMember

    Sunlight only hits a black side in the morning for about an hour,
    but it just gives the heater a little less to do, it stays a 24'c during that moment.
    It just seems to be too cold in the early morning, or atleast I think it is.
    Might still be that thermometer being a piece of junk.

    I'm a stickler for good automation, but multiple heaters seems like a bit overkill for a wee 20 gallon tank. :p
    My 50w heater seems to be hanging on, just barely, but I think ill just replace it with something better, come winter.

    I've been hovering the buy button on a tidal 55 for a while now, but im worried it ll face the same issue as my current filter.
    With no way to control flow, my tank is still gonna have dead spots.
    Last edited: Apr 19, 2019
  18. H2O ConciergeValued MemberMember

    I agree with you about 2 heaters in a 20g is overkill. I had a heater fail in a 60g once and had to deal with the consequences. I have bought what were reliable heaters only to find that their internal thermostats were not accurate. I relay on the controller as a safe guard on my larger tanks (50g & above) to monitor/alarm for abnormal tank temp. In my 5 &10gallons I have found these to be good. IMG_7996.JPG
  19. H2O ConciergeValued MemberMember

    The Tidal 55 has a decent range of flow control from about 50-250 gph. The Tidal 110 is 90-450gph. Of coarse as always it can vary depending on the media.
  20. kerwinNew MemberMember

    I wonder if there are any problems in the use of inkbird's products?