39 votes

My fish are disappearing :(

The most reasonable explanation is that it died and was eaten by the other fish / snails. Note that some snails are carnivorous. Many fish are cannibalistic if the opportunity arises. Some leftovers ...
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  • 1,945
35 votes
Accepted

Why don't fish grow to their full size in a small tank?

Fish excrete hormones in their waste. In a confined space like an aquarium, these hormones build up and act as growth inhibitors, this is basically an evolutionary mechanism, to prevent fish from ...
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  • 3,073
16 votes

How can I stop my turtle from eating my pet goldfish?

First, the turtles are eating the fish because fish are food, not friends. Turtles are omnivores and fish make up part of their natural diet. There's absolutely nothing you can do to stop it other ...
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  • 15.5k
14 votes

Why do fish tanks have closed roofs?

Nearly any cover you buy or build will allow enough air to circulate. If you're concerned, you can just leave a bit more space between the water surface and the cover, but this really isn't a big deal ...
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  • 3,853
13 votes

Would a small amount of bottled water mixed in with an aquarium harm the fish?

Don't panic, it's probably okay! The key thing here is that you caught the error and asked the question. I'll cover both bases here and try and explain a few things (forgive me if you already know ...
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  • 5,124
12 votes
Accepted

Is distilled or spring water better for fish tanks?

Distilled or reverse osmosis water does not have the minerals necessary to buffer pH. If used exclusively you will have a very unstable pH which is dangerous for fish. Spring water can vary in ...
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  • 537
11 votes
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Dried goldfish became alive after re-introducing into water

Goldfish can live for up to three hours out of water. It also depends on where your goldfish lands. If they landed somewhere moist or in the puddle of water they spilled out of their bowel, they can ...
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10 votes
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What is a "sump" when talking about aquariums?

A sump is basically just a low reservoir that collects water as it drains from something above it. When you hear the term used in an aquarium, it's referring to a reservoir that sits below the main ...
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  • 3,853
9 votes
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Why do you need to change the water in your fish tank?

One of the primary reasons for water changes is to remove harmful waste and chemical compounds from your tank that tend to build up over time. This is especially important in new aquariums where ...
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9 votes
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Does the shape of a fish tank make any difference?

Quite apart from the looks and size, which is how many people select an aquarium, different fish have different requirements. Some species need a lot of vertical space, others are happy to sit near ...
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  • 387
9 votes
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Why did my Guppies not grow for 8 months?

There are a couple of issues that I can see here that may be limiting how your fish grow. 1. Temperature You didn't mention having a heater for the tank and I cannot see one in the picture that you ...
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  • 5,124
9 votes

One discus fish bullying the other discus

I have to strongly suggest taking these fish back to the store. I've kept discus for many years and bred discus in the past for roughly a decade. I can say with almost complete certainty that these ...
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  • 3,073
9 votes

Where do you keep aquarium plants until you plant them in an aquarium?

Not only can you put your plants in another container, but you should. It is always a good idea to quarantine plants in a separate container for a few weeks before adding them to your tank, otherwise ...
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8 votes

How do I continuously change fish tank water?

You won't find anything that does this off the shelf at your local pet shop. It's possible to build it if you're an experienced plumber, but the short version is don't bother, just get a big canister ...
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  • 3,853
8 votes

Is distilled or spring water better for fish tanks?

I'm a marine biologist and have inadvertently done this experiment with toxicology tests on fish. Distilled water alone in a very clean container will kill fish quickly. It's not the lack of ...
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8 votes
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How well does an internal filter keep water oxygenated?

Oxygen is introduced into the aquarium through surface agitation. Filters which feed water back into the aquarium through some kind of waterfall like the one you linked to will agitate the water, ...
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  • 537
8 votes
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Why does the colour of Neon Tetras fade when they are resting?

Fish have cells called chromatophores that produce the pigments that give coloration or reflect light. The colour of a fish is determined in part by which pigments are in the cells (there are several ...
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8 votes
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Is it possible to put a hot water (boiled using the gas stove) in a fish tank?

More dangerous than it is safe. Certainly very stressful. Guoramis are quite difficult to keep and it is most likely that they'll suffer the most (you listed your fish in decreasing order of ...
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  • 2,466
8 votes
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What is this parasite?

Looks like a damselfly larvae to me, which isn't actually a parasite. It is, however, carnivorous... If your fish were larger, this larvae could have turned into food for them, but not in this case ...
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  • 20.3k
8 votes

What animal can be kept in a tank just under 3 gallons?

It is very hard to get a small tank to be in biological balance and to keep the water quality good, so I suggest you use this tank only for treating your fish with medication. This can be helpful if ...
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  • 18.8k
8 votes
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What is special about an aquarium using no carbon dioxide, no fertilizer and no filter?

It is special in a sense that most aquarium setups include a lot of equipment, mainly a filter; the filter facilitates cultivation of nitrifying bacteria that are responsible for neutralization of ...
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  • 105
8 votes
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Fish swimming with mouth always touching the water surface

Fish swimming with their mouth constantly glued to water surface is a sign that they are gasping for breath. However, the reason for them being short for breath usually isn't the low oxygen ...
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  • 105
7 votes

Why do fish tanks have closed roofs?

As long as it's not completely sealed air will get in. Oxygen getting into the water this way isn't so fast that it can benefit from being fully exposed to the air. Other reasons for roofs: ...
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7 votes
Accepted

How do I do a water change in my fish tank?

Water changes are almost what they sound like, you're changing the water in the tank. But, with very few exceptions, you never want to change more than 50% of the water in the tank. Water changes that ...
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  • 15.5k
7 votes
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Is there a way to test the amount of dissolved oxygen in a tank?

You can buy a dissolved oxygen meter, but they'll generally start in the US$200 to US$400 range, and a suitable one I believe runs closer to US$500-600. Not exactly an everyday piece of equipment for ...
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7 votes

Did my catfish kill my betta

The catfish we have in home aquariums, are generally docile, and non predatory. They cannot chase non catfish fish as they basically are not great swimmers. What happens is that, the aquarium catfish ...
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  • 399
7 votes

Is it possible to put a hot water (boiled using the gas stove) in a fish tank?

Well, yes, it is possible, but I wouldn't advice. Boiling water changes water hardness. Temporary hardness is mostly destroyed by mere boiling of water, when bicarbonates are decomposed, will ...
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  • 275
7 votes
Accepted

Best way to adjust fish tank water chemistry

Firstly, I'll go for my old refrain "consistency is key". It's better to have consistent water parameters than changing them continually to 'chase the perfect conditions'. Firstly, your nitrite ...
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  • 5,124
7 votes

Can I put newborn platies with neon tetras?

Neon tetras will attempt to eat these. I've kept neon tetras with shrimp and they would often pursue the baby shrimp. Luckily for the shrimp, they're pretty fast and hard to see so the fish would ...
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  • 5,124
7 votes
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What plant is this?

It is Caulerpa algae, although it has roots, stems and leaves (may be C. prolifera or C. floridiana). Tangs, Moorish Idols and other fish eat it. It grew very vigorously in my aquariums and so can ...
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  • 1,726

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