Aggressive Dalmatian Molly?

[Katenotkatie]

Hi, I have a 10 gallon tank with 1 Dalmatian Molly (about 3"), 1 GloFish Neon Tetra (about 1 1/2") and 3 snails. I am almost certain that my Molly is a male. Not sure about the Tetra... Anyway, my Dalmatian Molly (Domino) has been chasing my Glofish Neon Tetra (Tangerine) around the tank. He is a lot more active when the tank light is on, so that's when he usually does it. One time, Domino was chasing Tangerine so quickly that he slammed into the side of the tank and cut his face. The cut is pretty much healed, but will the scales grow back? And is Domino's behavior normal for a dominant male, or should I be worried? Domino hasn't been hurting Tangerine, just chasing him. I moved some stuff around in the aquarium, and I think it helped.

 

[CallMeIshmael95]

A grown molly really needs at least a thirty gallon tank because they like to swim so much. I've always kept mollies and I've never really thought them to be aggressive. Maybe he's feeling crowded and it's making him feisty.

 

[Katenotkatie]

Ok, but what should I do? I can't afford another tank and I really, really love Domino. Also, why do they need such a big tank? PetSmart said that a good rule of thumb is one gallon of water per inch of fish. Also, even though I've read that Dalmatian Mollies max out at 4 3/4 inches, PetSmart said they max out at 3 inches.

 

[Fishfur]

You and my niece, also Kate, would get on well. She's not fond of Katie either.

The one inch to a gallon rule really doesn't work. It was never more than a 'guesstimate' in the first place, now long outdated, but still repeated. I think Domino bullies the other fish, in part, because it is much smaller than he is. They aren't a good pair, the neon would be much happier with a half dozen other neons to school with.

The molly would be happier in a bigger tank, with another molly or two to hang out and chase around with.

At this point, you don't have any good choices. If you can rehome the neon, or even get store credit for it if you take it back, that at least would stop it being bullied, and Domino would not have anyone to bother. There really isn't much room for another fish his size.

I understand you love Domino, but the other choice is to rehome or try to get store credit for him, and get more neons to keep Tangerine company, which would make him and his pals much happier. Sometimes we need to do the best thing for the animal, even if it makes us unhappy or sad.

In future, the best thing is to research any fish you might like to have before you buy any. PetSmart and many other stores don't hire staff for their fish knowhow, they hire them to sell stuff. If you get good advice, that's a bonus, but you just cannot count on it. This is not a great way to learn this, but it is something we all have to learn.

Good luck. It's not an easy choice to make, but if you love something, you want it to have a good life, and should make a choice that allows the best chance for that to happen.

 

[Katenotkatie]

Okay, so re-homing Domino is not an option because I don't know anyone who has a fish tank besides my friend, but she has goldfish. Will PetSmart take fish back? It's past the 14-day warranty.
Also, Domino's aggressive behavior seems to have stopped. He swims around the tank normally, side-by-side with Tangerine. Could he be ok? He seems perfectly healthy, and the chasing has stopped. I moved some plants and stuff around, because I read that that can help stop fish aggression.
Do PetSmart Dalmatian Mollies max out at the normal 4 3/4" or 3", like they said?? How could they not know about the normal size of their own fish?

 

[Samzter]

Okay, so re-homing Domino is not an option because I don't know anyone who has a fish tank besides my friend, but she has goldfish. Will PetSmart take fish back? It's past the 14-day warranty.
Also, Domino's aggressive behavior seems to have stopped. He swims around the tank normally, side-by-side with Tangerine. Could he be ok? He seems perfectly healthy, and the chasing has stopped. I moved some plants and stuff around, because I read that that can help stop fish aggression.
Do PetSmart Dalmatian Mollies max out at the normal 4 3/4" or 3", like they said?? How could they not know about the normal size of their own fish?

I'm not in the us but if petsmart don't take him, you can look around other shops and see if they will. Or put a ad up on the Internet. The aggressive behaviour may have stopped, and he may look perfectly fine, but it won't be long until he isn't alright. If he is kept in a tank too small for him, the outside of his body will stop growing, but his organs will carry on and will cause lots of pain and then he would implode. I've read adult mollies have been known to reach sizes of up to 5 inches. So maybe it would be best if he was to be rehomed

 

[Delapool]

Does sound tricky. If the fish is still being bullied/chased after a week or so, then there is a good risk of fish death, particularly if he starts clamping fins. I also would think these fish would do better in a school, I wonder if they have been sorting out the pecking order? I think shifting the plants and decorations around is a good idea, it might break up any established territories. If the chasing is only in the morning say, then you could try changing light hours and time. I know the light pattern should be the same every day but something else to try if needed.

 

[Katenotkatie]

Domino hasn't been clamping fins or anything- just the chasing. Sometimes he'll be swimming side-by-side with Tangerine, like they're best friends or something. I don't think he'd actually hurt Tangerine.
By the way, my first post had a typo. Tangerine is about 2 1/2.
I want to get more fish, but there was this huge issue with my tank and bacteria and stuff... I had eight fish at the time, but Domino and Tangerine are the only survivors. Because of unbalanced water chemistry and stuff, I haven't been able to get new fish because of one thing or another. I was hoping that I could get more this weekend, but two of my snails died. WHY?! So now there's probably more bad stuff in the water and PetSmart is going to be all like, "Buy this, it might help. And this. And this." (That's where I test my water). Apparently, last time, the Ph was a little high - 8. PetSmart recommended this stuff to make it go down. But aren't you only supposed to mess with the Ph if it's dangerously high or low? It seems like everyone in PetSmart has different ideas on how to take care of fish.

 

[Delapool]

I think their would be others more experienced here but what were your test results for everything? Do you also have results for your tap water (or whatever you use for a water change)? What is causing the fish loss? For the tetra, ph does sound a little high and wouldn't like it to drift higher but pet shops here don't seem too worried as long as it is close to preferred ph range for that fish. Rapid changes are more of a problem I'm told so I agree that adding more chemicals can be the start of a slippery slope. I'm lucky that my tap water is to the specs I want. I have adjusted ph but found I was buying other chemicals and mucked the tank around a bit.. Now I just do more water changes.

 

[Katenotkatie]

So, I had 8 fish. Then the heater broke. The temperature went down to about 65 degrees, maybe lower. A lot of fish died. But, they died in the middle of the night, so I found them dead when I woke up in the morning. Lots of bad bacteria from the dead fish got into the tank, making the remaining 4 or 5 fish sick. All of the other fish died, besides Domino and Tangerine. They were doing REALLY badly. Domino was lying on his side on the bottom of the tank and Tangerine suffered from fin and tail rot and his/her tail fin was almost completely gone, no doubt what killed Strawberry, my other GloFish Tetra and Tangerine's best friend. But I got this medicine stuff from PetSmart and within a day, my fish were better. Domino recovered the quickest, mainly because he will eat anything put into the tank; he even tried to eat the floating plants in my tank (luckily he spit it out, haha). I'm getting my water tested tomorrow; I will post the results then.

 

[Fishlover3578]

Did you do a partial WC on tank after finding dead fish ?

 

[Khuligirl93]

So it sounds like you have a number of things going wrong here. When fish die, or any organic matter decomposes in your tank (poop, excess food, etc) it releases ammonia, not bacteria. Certain kinds of bacteria are actually very good for your tank and necessary to have a healthy tank. This is why we need to cycle tanks before adding fish. My guess is that's why all your fish died at once, because there was an ammonia spike. There are two kinds if bacteria: a kind that converts ammonia into nitrite, and a kind that converts nitrite into nitrate. The process of growing these bacteria is called cycling. (you will need to get the API freshwater master testkit in order to monitor this process). These bacteria are veeery important because they prevent fish from getting poisoned by their own poop. Also weekly 25-50% water changes with a gravel siphon are critical. Try reading this article on cycling: http://www.aquariumadvice.com/i-jus...g-but-I-already-have-fish-What-now/Page2.html And yes, nornally Petco and Petsmart employees don't know very much about these things. They generally just want you to spend your money buying things. So don't trust them- ask on this forum first Also, as other people have already told you, a 10 gallon is a bit too small for a Molly. And tetras are schooling fish so they like to be in big groups. One thing that might help tangerine is if you add some more plants to create more hiding places for him though.

Edit: also, mollies are omnivores which means they eat both meat and plants. This is why domino tried to eat your floating plants. Having some vegetable matter in their diet is good for them, so try feeding him some boiled peas with the outside peel taken off and squished a little bit my mollies always loved that. I've heard people say to feed them lettuce and steamed broccoli but my mollies have never showed any interest in those.

 

[Fishfur]

It's not that Petsmart does not know what size their fish might grow to. It's that they have to say a size and it can vary depending on the actual genetic makeup of the fish and how it was raised. Some mollies, if they are bred & raised in large ponds, can get to be nearly a foot long. Their fry are much larger as well. It's due to being raised in a much larger area than fish in a tank would ever have.

And most mollies in the aquarium trade today are hybrids, not pure bred species. There are several species of them, the two most common ones being Sailfins and one other, and the species name escapes me just now. Sailfins get much larger than the other species does, and Dalmations have Sailfin genes. So while Domino might only grow to 3 inches, it's quite possible he could get to 5 or even 6 inches.

But fish kept in tanks that are too small for them can become stunted. I doubt a fish would implode, but it's a very uncomfortable life for the fish, and can't be reversed.

As for Petsmart taking either fish back, they might be willing to give you credit for a portion of the price. You are not taking it back due to warranty issues, you are taking it back because you don't have the right tank for the fish. Most stores that sell fish will take back fish they sold if there is a problem like this, but they will only give you credit for a percentage of the selling price.

Some credit is better than no credit, and it will solve the problem of Domino eventually outgrowing the tank he is in now. Then you could get some other small fish you could enjoy, that won't outgrow your tank.

And if at all possible, you really should have your own test kits. If you have an ammonia spike, by the time you can take a water sample to the store, it's likely too late for the fish. I know the tests are not cheap, but they do last a long time and you get a lot of tests in one kit. The API master kit is a good one, and is cheaper than buying all the tests it contains separately.

You have certainly had your troubles with this tank. You have also had some bad advice from the Petsmart store. As I said earlier, you really cannot rely on the store staff for advice. They are there to sell you stuff, and they want you to spend money. Best thing is to get the test kits, make sure your tank is cycled and all is working well. See if they will give you credit for Domino and Tangerine and start over with fish you can keep healthy and enjoy for a long time.

And while I don't mean to be unkind, there is something else you should know. You say Domino and Tangerine are the only survivors of what must have been an ammonia spike. Your description of Domino when that happened makes it clear he was exposed to high levels of ammonia for some period of time. It wouldn't have been bad bacteria, as you thought, it would have been ammonia, as the other poster explained.

Because of this, even though they are alive for now, both these fish have been damaged by the ammonia they were exposed to. Chances are unfortunately very high that both of them will die much sooner than they should. It can happen weeks or months after the ammonia exposure takes place. Sometimes people wonder why the fish has died, seeing no reason at the moment, because they forgot it was exposed to ammonia earlier on.

So if you can get credit for one, or both of the fish at the store, even if it's only for a small portion of what they cost originally, you will save yourself the unhappy experience of seeing them die as well. I think it is best that you know what is very probably going to happen, based on what has already happened to these fish.

 

[Katenotkatie]

So it sounds like you have a number of things going wrong here. When fish die, or any organic matter decomposes in your tank (poop, excess food, etc) it releases ammonia, not bacteria. Certain kinds of bacteria are actually very good for your tank and necessary to have a healthy tank. This is why we need to cycle tanks before adding fish. My guess is that's why all your fish died at once, because there was an ammonia spike. There are two kinds if bacteria: a kind that converts ammonia into nitrite, and a kind that converts nitrite into nitrate. The process of growing these bacteria is called cycling. (you will need to get the API freshwater master testkit in order to monitor this process). These bacteria are veeery important because they prevent fish from getting poisoned by their own poop. Also weekly 25-50% water changes with a gravel siphon are critical. Try reading this article on cycling: I just learned about cycling but I already have fish. What now?! - Aquarium Advice And yes, nornally Petco and Petsmart employees don't know very much about these things. They generally just want you to spend your money buying things. So don't trust them- ask on this forum first Also, as other people have already told you, a 10 gallon is a bit too small for a Molly. And tetras are schooling fish so they like to be in big groups. One thing that might help tangerine is if you add some more plants to create more hiding places for him though.

Edit: also, mollies are omnivores which means they eat both meat and plants. This is why domino tried to eat your floating plants. Having some vegetable matter in their diet is good for them, so try feeding him some boiled peas with the outside peel taken off and squished a little bit my mollies always loved that. I've heard people say to feed them lettuce and steamed broccoli but my mollies have never showed any interest in those.

The food that I give my fish is intended for omnivores. It has kelp and other plants in it.

 

[Katenotkatie]

Ok, so what I'm going to do is get more plants and more Tetras. From what's been said, Domino and Tangerine have not-so-long lives ahead of them. In the amount of time it would take to find them a good permanent home, they could be dead already. I don't know anyone else who has a fish tank who can handle fish like mine, and I don't trust PetSmart with them. After all that's happened, I honestly think they'd be happier with me. Giving them a completely new home would be a bit of a shock, wouldn't it?

 

[Delapool]

I agree with tetras but for the ph which I think at 8 is getting high for them. Group thoughts? I've never kept them that high. Would still be interested in your water specs for the tank and whatever you use for water changes.

 

[Katenotkatie]

I'm hoping that the Ph will go down on its own. The water in my tank is a little soft and since when the Ph goes down, the hardness of the water usually does, too, so I don't really want to mess with that stuff unless the Ph becomes dangerously high.

What are everyone's thoughts on me keeping Domino and getting more Tetras? Will getting more fish be good or bad for Domino's current condition? By the way, it's been multiple weeks of chasing and still, Domino hasn't once hurt Tangerine. I honestly do think they care about each other, but Domino just sometimes gets ticked off at Tangerine. Tangerine seems a little lonely and keeps bugging Domino. Sometimes Domino chases Tangerine away, sometimes he will just swim alongside her/him.

 

[Fishfur]

It's very hard to answer this kind of question, especially when we don't really know the true parameters of your tank water. I confess I'm a bit puzzled to hear you say the water is soft, since higher pH ranges are usually associated with hard water. Soft water is usually acidic in pH.

So long as you are doing water changes, the calcium buffers in the water will be replenished, so you should not have any major changes in pH. So, unless you add something to the water yourself that would increase pH, it's not going to get dangerously high. If you don't add anything to it, I don't see how the pH can rise any higher than it is when it comes out of the tap at first. Then typically the pH from the tap drops at least a few points within a day or so.

You are correct that messing with the water trying to adjust it to a particular pH reading is quite hard to do, and often does not work. But if you tried to adjust it to suit the tetras, which would mean lowering the pH and softening the water, Domino isn't going to enjoy that at all.

Since you have one tetra surviving in this water as it is, I suppose some other tetras could also live in it. But whether Domino gets along with more tetras is hard to say. He might not bother them, or he might bully them. There is really no way to know before you try it.

In the end it's your money, and your tank. If you don't want to invest in the tests so you can monitor water yourself, of course that is your choice. But it does make it more difficult to give advice on how fish might do, when that kind of information is not available.

If you do add more tetras and they do ok, I would expect that Tangerine would hang out with them and probably not bother Domino much.

 

[Katenotkatie]

Yes, I thought that, too. I told my fish that I'd be getting some friends for Tangerine and maybe a new snail. They seemed pretty happy and Domino hasn't chased Tangerine since I said that. By the way, speaking of snails, is it normal for Domino to poke the snails? He used to do that all the time back when I had 3 snails. He would poke their shells and sometimes even their feet. He enjoyed knocking them off the side of the tank. He seemed to pick on my smallest snail, Butter, the most. Do other fish do that, too? Is the poking dangerous or bad for the health of the snails?

 

[Katenotkatie]

Did you do a partial WC on tank after finding dead fish ?

Yes, I did. I have also done many water changes since then.