Fish jumping

[dR3ws3r]

Hello all,

I've had a 25 gallon cube set up for about 2 years now. Mostly just neon tetras in it. Well planted, decently scaped, plenty of places for the neons to hide or keep shaded from the light. Things have been pretty stable for quite a while and I had about 15 neons in there. Over the last month, I have had 3 fish jump out of the tank and die. I have not changed anything in the tank recently. Their overall behavior seems to be the same in general (as best as I can tell). They do seem to be "spooked" when I do partial water changes in the mornings when the light is not on. (I do 5 gallon changes about every 2-3 days). There is no lid on the tank. I just do morning changes as it is the most convenient for me.

Recently I did move the tank about 5 feet from one wall to another, but the general lighting should be exactly the same.

I can think of two or three different things going on, but maybe someone else can have some insight?

I have tended to keep the water level about an inch or so from the top of the glass to avoid the noise of the lily pipes splashing water.
They seem kind of jumpy when I do the water changes. They react to the gravel cleaning tube and kind of dart about. I caught one stuck to the glass during a recent water change.

I do use RO/DI water that is re-mineralized because my local water is not good. The PH and other chemistry really can vary quite a lot with my local water. If I leave the tap water in a bucket, a milky white film builds up on it. Someone thought it might be anti-corrosion chemicals. Despite my constant contact with my water authority, I gave up complaining, and just have taken this path with RO/DI. I have been doing the RO/DI remineralization for about a year now.

It is probably a tough question, but does this new behavior mean I have a water problem? Are there vented lids that people can recommend? Any thoughts or ideas?


Thanks for reading,

 

[Slaphppy7]

Get a glass lid.

They are sold hinged, with a plastic section on the back that you can cut out portions of to allow equipment to pass through.

 

[Back in the fold]

Fish can be spooky. Most of them don’t like surprises. I have fish that I have had for a couple years or more and they still freak out on occasion.

 

[CaptainBarnicles]

I gave up with hoodless tanks, the evaporation and the constant fear of finding fish on the floor just about made me crazy

 

[Naughts]

does this new behavior mean I have a water problem?

Not necessarily but water problems do cause fish to jump more. Do some tests to rule some things out (or not).
But fish jump, that's why most tanks have lids.

 

[Back in the fold]

I gave up with hoodless tanks, the evaporation and the constant fear of finding fish on the floor just about made me crazy

One of my Granddaughters has an open aquarium and I was very surprised at the amount of evaporation that happens. It’s a twenty high heated with a preset to 76 heater. The room is much cooler and I think that has something to do with it. Some science buff might be able to explain the why of that but all I know is that she replaces a gallon a week. Surprisingly she’s never had a jumper but she keeps the water level about three inches under the rim.

 

[Byron]

There are a couple issues here, others have mentioned some of them. Open tanks are not advisable, as fish do jump especially at night, dust will settle on the surface, water evaporates and gets into the room/building structure, pets (cats especially) may land in the tank, the water temperature will not be the same as with a cover (this can depend upon time of year and fish being kept (anabantids for example must have it covered to keep the air warm).

Never do work on the tank with the tank light off. When the light comes on in the morning, give the fish 30 minutes minimum, up to an hour, to adjust to the light difference. Then do the water change. I had far more skittishness if I ever did something when the tank light was off.

Water changes must use water that has the same parameters as the tank water, relatively speaking. Parameters means GH, pH and temperature. A significance difference in any one of these can stress out fish, and worse.

 

[Ichthys]

Since you moved the tank could they be picking up vibrations from the floor that they weren’t before (ie loose floorboards…?)

It’s not common but sometimes there can be a position in a room where a tank will not be successful. Move it to another wall and it will be. Something to do with the electromagnetic field of the house and it’s wiring? (a guess)

 

[Ellie11]

Hello all,

I've had a 25 gallon cube set up for about 2 years now. Mostly just neon tetras in it. Well planted, decently scaped, plenty of places for the neons to hide or keep shaded from the light. Things have been pretty stable for quite a while and I had about 15 neons in there. Over the last month, I have had 3 fish jump out of the tank and die. I have not changed anything in the tank recently. Their overall behavior seems to be the same in general (as best as I can tell). They do seem to be "spooked" when I do partial water changes in the mornings when the light is not on. (I do 5 gallon changes about every 2-3 days). There is no lid on the tank. I just do morning changes as it is the most convenient for me.

Recently I did move the tank about 5 feet from one wall to another, but the general lighting should be exactly the same.

I can think of two or three different things going on, but maybe someone else can have some insight?

I have tended to keep the water level about an inch or so from the top of the glass to avoid the noise of the lily pipes splashing water.
They seem kind of jumpy when I do the water changes. They react to the gravel cleaning tube and kind of dart about. I caught one stuck to the glass during a recent water change.

I do use RO/DI water that is re-mineralized because my local water is not good. The PH and other chemistry really can vary quite a lot with my local water. If I leave the tap water in a bucket, a milky white film builds up on it. Someone thought it might be anti-corrosion chemicals. Despite my constant contact with my water authority, I gave up complaining, and just have taken this path with RO/DI. I have been doing the RO/DI remineralization for about a year now.

It is probably a tough question, but does this new behavior mean I have a water problem? Are there vented lids that people can recommend? Any thoughts or ideas?


Thanks for reading,

I’ve heard some tragic stories about Oscars and Dojo Loaches jumping out, as well as other species. I use glass hinged lids. They come with a plastic rear section that can be cut out for hosing, HOB filters etc. I use plexiglass to cover open gaps.

What kind of hood does a 25 G cube have? If I had something with gaps like your seems to have I’d have Lowe’s cut a piece of glass that can be laid over the entire top, maybe with a 1/2” overhang. This is a cheap quick solution. Alternatively, you can use plexiglass or buy a hinged lid that is the closest size for the cube. Right now I have a glass hinged lid for a 40 G tank on a 20 G tank. I had to isolate an aggressive fish and used equipment laying around. This oversized lid is not a pretty sight, but no way that fish is taking a flying leap.

I do one big water change weekly, about 60%.

Do you use something like the API freshwater master kit to test ammonia levels, nitrates etc? My tap water has a very low nitrate level, but it’s otherwise good.

 

[dR3ws3r]

Since you moved the tank could they be picking up vibrations from the floor that they weren’t before (ie loose floorboards…?)

It’s not common but sometimes there can be a position in a room where a tank will not be successful. Move it to another wall and it will be. Something to do with the electromagnetic field of the house and it’s wiring? (a guess)

I can't say absolutely, but it is really unlikely as the tank didn't move too far. There is nothing around the tank or below (in the basement) that is mechanical.

As there had not been any jumpers for quite some time, and now there have been a few, I was surprised. Which led to my post. Mostly everything else has remained pretty constant, including scheduling of water changes, feeding, lighting, etc.

When I add the re-mineralizing powder, I try to weigh it on a small digital scale each time, but the water in the bucket could be slightly more or less each time. I do try and maintain a constant tdh of the "new" water I am using, but it's not really possible to be totally exact, as there always appears to be some lag between the initial value and some final value you arrive at depending on how well it mixes, and how long you wait.

 

[CaptainBarnicles]

One of my Granddaughters has an open aquarium and I was very surprised at the amount of evaporation that happens. It’s a twenty high heated with a preset to 76 heater. The room is much cooler and I think that has something to do with it. Some science buff might be able to explain the why of that but all I know is that she replaces a gallon a week. Surprisingly she’s never had a jumper but she keeps the water level about three inches under the rim.

Urgh! The evaporation and with hard water you've got the mineral deposits to contend with. Trying to scrape at that every week was literally like nails on a chalk board never again.

Interesting thought regarding your granddaughter's tank maybe it's more to do with the humidity levels in her room rather than temperature?

 

[Ellie11]

No lid = heat loss & evaporation & risks jumping

 

[Colin_T]

As Byron said, never do water changes on a dark tank. Fish see big shadows coming towards them and freak out. It might only be your hand or a gravel cleaner but it can be enough to cause fish to flee, and that often involves going over the wall. This is made worse if the fish are asleep and get woken up and startled. Let them wake up and then do water changes.

Make sure the gravel and filter is clean. Make sure there is no ammonia or nitrite, and the nitrate is less than 20ppm.

Fish do get use to their surroundings and moving a tank (even only a few feet) can mess up their routine and take them some time to settle back down. It's a bit like when people move to a new house. You go to bed in the new bedroom and might wake up during the night reaching for the light switch but it isn't there. You become a bit disoriented and the same thing happens to fish.

TURNING LIGHTS ON AND OFF
Stress from tank lights coming on when the room is dark can be an issue. Fish don't have eyelids and don't tolerate going from complete dark to bright light (or vice versa) instantly.

In the morning open the curtains or turn the room light on at least 30 minutes (or more) before turning the tank light on. This will reduce the stress on the fish and they won't go from a dark tank to a bright tank instantly.

At night turn the room light on and then turn the tank light off. Wait at least 30 minutes (or more) before turning the room light out. This allows the fish to settle down for the night instead of going from a brightly lit tank to complete darkness instantly.

Try to have the lights on at the same time each day. Use a timer if possible.

If you don't have live plants in the tank, you only need the light on for a few hours in the evening. You might turn them on at 4 or 5pm and off at 9pm.

If you do have live plants in the tank, you can have the lights on for 8-16 hours a day but the fish and plants need 8 hours of darkness to rest. Most people with live plants in their aquarium will have the lights on for 8-12 hours a day.