Hi peeps,

Following on from a post on the c/w forum, my tank temp this morning is 30 degs. I turned the heater down on Sunday, but its just going up. The house is still very warm, despite every window & door being open.

-Should I be concerned about this or just wait for the temps to drop gradually?
-Should I do a water change or will that just stress my fishies out? I did a water change on Saturday.

Fishies seem ok, behaviour seems norm.
As I have 2 little girls, we always do what we can to keep the house cool anyway.

I just wasn't sure whether this cold be a prob for tropicals too.

Ta very much

It depends entirely upon the species. Some "trops" will live at 30c naturally. Other species sold in the trade are not really tropical fish at all and could die from such temperatures if they have to endure it for prolonged periods.

I have had to install chillers on two of my tanks containing sensitive species. They get used for a week or two each year!

You could look at investing in one of them. Temps upto 30c are usually not fatal for most species if it's for short periods of times though. Remember, in the tropics it's not uncommon for wild fish to experience heat waves on occasion too. That said, you should make every effort to stay on top of the temperature. The addition of a small air pump can make a large difference to the amount of dissolved oxygen in the water, so if you don't already have one, get one. Small water changes will not hurt.

My cold water aquarium rose from 19c to around 26 yesterday, had no effect when I put. The fan on even after 6 hours..it's 22 today.

I have platys & mollies & they're fairly hardy. I did think of the 'occuring naturally in oceans' thing, but took the view that an ocean is a huge body of water & they're not going to experience large temp differences in the same way as a tank.

I already have an air curtain, so that's covered.
I didn't even consider putting a fan on it as the fans were on my daughters last night & the room temp only dropped by 1 degree!!!

A fan won't reduce the tempreature of the water. It will only circulate the air around it. It will feel coller to you but will little to no effect on the aquarium I'm afraid. You'd need a domestic air con unit instaled to make any real difference.

I've seen a couple of marine fan set ups that "claim" to be able to drop the temp by 3 to 4 degrees. Either that or a marine chiller unit would work (like INJAF suggests)

You can pick up domestic air con units for much less than a marine chiller unit. I'd say that's probably the best choice - and the bonus is you get cooler too

I've tried the fan trick myself - it does make a bit of a difference but maybe it depends on how you 'attack' it as it were. I turned all the tank lights off and pushed the light bars to the back of the tank (if you have more than one light bar like I did at the time you might have to remove one or stack it on top of the other one). I took the lids off (mine are in several sections and just rest on the tank) then employed some hi-tech engineering skills and balanced a tea tray on the end of the tank with a fan sitting on that - fan directed at water - and had the flow from the fan running along the length of the tank. It's quite a big fan, about 12" diameter.

I've got one of those Aquaminder thermometers - it's a digital reading with a sensor on a long wire - the sensor was quite deep in the water so wasn't reading the surface temp. The temp dropped by about 2 degrees at least.

Caveat - if you utilise the tea tray/fan arrangement and it falls in the tank and disaster ensues it is not my fault! Electricity and water are not good bed fellows!

There are several variations on a theme of tank cooling, marines seem to use PCB fans mounted in DIY arrays as well.

Totally irrelevant but I have a strange aversion to air con, I'd rather be hot. Air con is a weird, there's something not right about it.

Fans increase evaporation from the surface of the water. Its kind of like cooling down by sweating. Another bonus is that it should dissipate some of the heat from your lights. Its not going to have a huge effect (I think I'm seeing about 2 degrees difference) but its cheap and won't cause harmful temperature fluctuations.

Quote:

Nutter

I have an aversion too Suey Partly because it's so American, and partly because it seems pointless with the amount of truly hot days we get.