warm weather & tank temperatures

Vorpal

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Hi everyone,

I live in Norway, and it doesn't usually get hot here, so we don't have air conditioning or anything where I live, and the last few days, it has been 28 C (82 F), and even with the lights off and heaters unplugged, our tanks are a little warmer than that. They started the day today at 27.7 C, so I added a little cool water over 30 minutes to bring them down to 27, and now they are back up to 28.5.

I am worried about a long period of such hot weather. We are predicted to have 30 C tomorrow. While I am home, I can keep an eye on the temperatures and add cool water as needed, but when I am at work I can not do that.

Also, if the lights are off all the time, the plants will suffer.

So, my questions:
-how long can I leave the lights off without killing my plants? They get very little natural light.
-how warm is too warm? We have Corydoras Sterbai and Swordtails
-is there anything else I can do to keep tank temperatures down?
 
lol 28C, we have summer temperatures over 40C here and the fish are fine :)

On a serious note tho, plants will need some light but can go for a day or two without any light. Have the lights on for a few hours at night and it will help.
Raise light units above the tank a couple of inches so heat can circulate around them instead of going into the tank.
Drill a 10mm hole in the top or side of the light unit near the ends so heat can come out.

Turn aquarium heater off.

Remove the hood from the tank if you have one. Remove coverglass too if you don't have fish that jump.

Have a fan in front of the tank blowing air over it.

Increase aeration and surface turbulence to maximise oxygen levels in the water.

If you live in a safe neighbourhood, open doors and windows up at night to cool the house down. In the morning close doors, windows and curtains to stop heat coming in. If you have a computer or television in the room, turn them off because they produce a lot of heat.

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Corydoras can tolerate 28C for a couple of months without any problems. Swordtails can tolerate 32C for months without any problems.

27-28C is fine and I wouldn't worry too much about it. If the water hits 30C for a couple of weeks then worry.

If you freeze some 2 litre plastic bottles, you can put one in the tank until it is nearly defrosted. Then put another in the tank. The defrosted bottles can be refrozen and used again when frozen. But you only need to keep the temperature below 30C and the fish will be fine. :)
 
I agree with most of post #2, the exception being the last item. It is better to have consistency and not up and down during a 12 hour period. Putting in cold water or frozen ice packs is not a good idea unless you can continue it so that there is no major fluctuations. A degree or two is not going to hurt, but do the other things mentioned to lower the room temperature (the tank will always be at room temperature over time aside from heaters and such) and/or tank (additional aeration, lights off some, etc). Do not do water changes that suddenly shift the temperature.

Temperature drives a fish's metabolism so it is very important. Fluctuations that are significant over short time periods are detrimental to many fish. Feed fish less (skip days if continuing hot weather) and avoid any stress.
 
lol 28C, we have summer temperatures over 40C here and the fish are fine :)
Its different when everything is geared up for cold weather. (I grew up in a hot climate).
Some time ago I worked in Denmark for a few years. Not nearly as cold as Norway but all the buildings are incredibly well insulated and no aircon anywhere (not even in offices). 2 weeks in the low 30s makes it absolutely unbearable indoors. We used to get a cab home in summer just for the aircon. Many evenings were spent in the city fountains - the local pubs obligingly sent waiters around with trays of beer.

Not much point in waiting for sunset either because its close to midnight by midsummer (and again Norway is further North)
 
For most of my fish keeping career I never had air conditioning either. My first fish room was a brick & concrete garage that got bitterly cold in winter and pretty warm in summer. We would get a couple of weeks of 40C+ temperatures and it was hot inside or outside. The tanks were regularly on 30C+.

Most petshops don't have air con in their fish rooms either. You go in dry and come out 10 minutes later and you are sweating. And most fish rooms are insulated so they hold the heat for a while :)

Move forward 20yrs and I had ponds outside on a concrete slab and they hit 40C+ in summer. The water actually hit 42C on a few occasions. The ponds had a corner sponge filter and a few plants and were in full sun for most of the day. The fish were fine and did well. The same ponds in winter dropped to 3C when it got really cold. The fish got brought inside when it was 10C tho.

I had a photo somewhere but can't find it now, and the temp in our games room where I had a couple of tanks was 56C. Fortunately it was only that hot for a couple of hours and cooled down after sunset.
 
I wondered about temperatures in the wild, given that swordtails are tropical.

We've got windows open and fans blowing. It won't work to close up the house during the day. It will stay cooler with windows open and fans blowing. If we close the house up, it will get very hot.

I can't easily raise the lights. I might be able to do something in a couple of days. I can take the hoods off. I hadn't thought of that.

Thanks for the advice.
 
The easiest way to raise a light unit off an aquarium is with little strips of wood about 1/2 to 1 inch square. Just put a length of wood under each end of the light unit. Then drill a 10mm hole in each end of the light unit and the air can flow up into the light unit (from underneath it) and out the holes in the ends. This means the heat from the light will go up instead of being trapped between the light unit and coverglass, and it won't warm the water.

The cool air moving over the light globes will also help them last longer :)

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When I use to collect fish down south in Western Australia I would take water temperatures at the collection sites. I regularly found water ways that were 32C or more. I found a pond with cold water fish in and the water was 36C in the shallows and 26C in the deeper sections. And I caught young fish in the shallow 36C water.

Most fish can tolerate 30C for quite a while as long as the temperature goes up slowly over weeks or months. And as long as there is sufficient oxygen in the water. The warmer the water, the less dissolved gases it can hold and this means less oxygen. Increasing surface turbulence helps a lot in these situations.

Having a clean tank, gravel and filter also make a difference in warm water. Bacteria (good & bad) grow faster in warm water. And bacteria use lots of oxygen and produce heaps of carbon dioxide. If you keep the gravel, filter and water clean, there will be fewer harmful pathogens and less bad bacteria using oxygen, and that leaves a bit more oxygen for the fish.

Filters don't just hold beneficial bacteria to convert ammonia into nitrite then into nitrate. They hold fish poop and bad bacteria grow in/ on that. By cleaning filters regularly you reduce the amount of poop in them and reduce the bad bacteria. The same with gravel cleaning the tank. The cleaner the gravel the less poop and less bad bacteria using oxygen :)
 
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I usually just rinse the (sponge) filters off in tank water when I do partial water changes. Should I replce the filter material?
 
I usually just rinse the (sponge) filters off in tank water when I do partial water changes. Should I replce the filter material?

No, you don't need to replace it, just make sure it's not over dirty or clogged with waste :)
 
No, you don't need to replace it, just make sure it's not over dirty or clogged with waste :)
Actually I would put it a bit stronger than that :)
You SHOULD NOT replace these. if you do you are throwing out the beneficial bacteria that has built up in them which could cause major problems.

Only replace when absolutely falling apart, and then not all at once.
 
I thought there was enough beneficial bacteria in an established aquarium that the filters could be replaced?

I don't usually. I rinse them out every week or two with water changes. I'm curious for when I do need to.
 
99% of beneficial nitrifying bacteria live in filter media like sponges, noodles and even carbon that's been in a filter for a month or more. There are small numbers of bacteria on hard surfaces in the tank that have water moving over them but the majority is in the filter materials.

If you have a new tank then it takes a while for bacteria to get into the tank and develop there. Tanks that have been running for more than 6 months usually have a lot of bacteria but not always good bacteria. The slime on objects/ glass in the tank is biofilm and is home to all sorts of bacteria, protozoans, viruses & fungus. Compare that to the sponges in a healthy power filter that contain primarily half a dozen species of bacteria that consume ammonia and convert it into nitrite and nitrate.

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Once established, filters should be cleaned at least once a month, more often if possible. The less gunk in the filter and filter materials, the fewer harmful pathogens living in them and the cleaner the water will be. Most of the gunk in the filter is fish poop and the water they live in is flowing through that. So the less poop in the filter, the cleaner the water.

If you have to clean the filter more than once a month due to it blocking up, then you need more filtration on the tank.

You can clean established filter media once a week if you like. However, most people do the filter every 2-4 weeks. Fortnightly would be fine.
 
I thought there was enough beneficial bacteria in an established aquarium that the filters could be replaced?

I don't usually. I rinse them out every week or two with water changes. I'm curious for when I do need to.

90% or maybe even more of your bacteria are in your filter media.....thats why you should not replace it until absolutely nessessary.....i have some filter foam that is 4-5 years old
 

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