New mollies all acting weak

[guppypups]

So I recently got a group of mollies, 7 of them from a breeder. When I got home I acclimatized them for 30min and released them into the tank. They all swam to the bottom and grouped together behind a large ornament. I figured they might be shy or adjusting so I wasn't too worried, my tetras had hidden for a day or two too. However, now its been just over a week and they're still acting weird! And its not just one or two, its the whole group. One of them died right away too!
I've talked to the previous owner and he suggested a 30% water change which I had already done just in case. I'm still waiting for him to tell me his tank's temperature in case the mollies are used to a different temp.

Water parameters.
ammonia - 0.0
nitrate and nitrite - unfortunately, don't have this tester
PH - 6.7
temp' - 26 C or 79 F
Hardness - I'm not sure. I just use tap water + conditioner and the tap water is supposed to be 11.6 grains per gallon

2. A full description of the fishes symptoms:
- All 6 of them hover slightly above the bottom or even rest on the gravel, staying upright but unmoving. They only act normal at feeding time or first thing in the morning they seem fine and active.
- One or two of them has a clamped fin
- At least they are still eating
- No white spots, fungi, or anything else as far as I can tell
-One of them dances weirdly in front of my tiger barbs, but its just the one so I don't know if its related to whatever is affecting them.

water changes
- every 2 weeks, 20-30%

chemicals and treatments:
Small amounts of aquarium salt as a tonic, added during water change

Tank mates
2x tiger barbs, 4x ember tetras, 1x small pictus catfish (5") and 1x pleco (8")

Tank size. 20 gallons

 

[guppypups]

So I recently got a group of mollies, 7 of them from a breeder. When I got home I acclimatized them for 30min and released them into the tank. They all swam to the bottom and grouped together behind a large ornament. I figured they might be shy or adjusting so I wasn't too worried, my tetras had hidden for a day or two too. However, now its been just over a week and they're still acting weird! And its not just one or two, its the whole group. One of them died right away too!
I've talked to the previous owner and he suggested a 30% water change which I had already done just in case. I'm still waiting for him to tell me his tank's temperature in case the mollies are used to a different temp.

Water parameters.
ammonia - 0.0
nitrate and nitrite - unfortunately, don't have this tester
PH - 6.7
temp' - 26 C or 79 F
Hardness - I'm not sure. I just use tap water + conditioner and the tap water is supposed to be 11.6 grains per gallon

2. A full description of the fishes symptoms:
- All 6 of them hover slightly above the bottom or even rest on the gravel, staying upright but unmoving. They only act normal at feeding time or first thing in the morning they seem fine and active.
- One or two of them has a clamped fin
- At least they are still eating
- No white spots, fungi, or anything else as far as I can tell
-One of them dances weirdly in front of my tiger barbs, but its just the one so I don't know if its related to whatever is affecting them.

water changes
- every 2 weeks, 20-30%

chemicals and treatments:
Small amounts of aquarium salt as a tonic, added during water change

Tank mates
2x tiger barbs, 4x ember tetras, 1x small pictus catfish (5") and 1x pleco (8")

Tank size. 20 gallons

UPDATE
The previous owner has the same water temp and similar hardness. He didn't use conditioner and I do but that shouldn't be the problem should it?
He swears they are just adjusting but it's been a week
Help

 

[Byron]

I do not agree with the "previous owner" here.

First, your water is on the acidic side and this always harms mollies. I assume the GH may be on the soft side (soft water and acidic water usually go together) and this is very detrimental to mollies. I am not saying this alone is the issue, but it does weaken the fish the longer they are in the water, and this will make it more difficult for them to deal with any other issue. What is the GH of your source water? This is absolutely crucial for mollies.

Nitrite and nitrate are important to test for. Mollies are very susceptible to ammonia, nitrite and nitrate. Temperature is OK as far as the mollies are concerned.

Second thing is you have a problem combination of fish in this tank. Tiger Barbs are aggressive fish, and they can easily frighten mollies even if no physical contact occurs. Same holds for the pictus catfish. Ember Tetras are much too small to have in with the pictus, this is certain to become a problem.

Tiger Barbs should be in a group of at least 8, with 10-12 or more better, and this group in their own tank which must be minimum 30 gallons. In a larger tank other species can bee added, but with careful selection to avoid any sedate fish or fish with flowing fins. Mollies are not acceptable tankmates for tiger barbs.

Pictus catfish also need a group of five minimum, four might work. But this fish gets largish, close to five inches, and a 4-foot tank is minimum. It is nocturnal, so many upper fish will be stressed by this activity.

Salt might help the mollies temporarily, but it is not good for any of the other fish mentioned, quite the reverse.

Ther mollies should be separated out ASAP inbto a tank of water that has a GH of 12 dGH or higher. They are not going to be healthy or last very long in softer water, if that is what you hav, and the acidic pH would suggest this.

 

[Essjay]

the tap water is supposed to be 11.6 grains per gallon

If that figure is accurate, it converts to 11.1 dH and 200 ppm.

 

[Colin_T]

It's probably pH shock if you have a pH below 7.0.

Mollies need a GH above 250ppm and a pH above 7.0. If you put mollies in acid water they freak out and die really quickly.

Check the pH of your tap water. If your tap water has a pH below 7.0, you will need to raise the pH in the tank if you want to keep the mollies alive. A couple of bits of limestone, dead coral rubble or some shells put in the tank or filter will help raise the pH a bit. Add a few bits and check the pH after a week. If it's still below 7.0 then add some more limestone, shells or dead coral. Continue adding it until the pH sits just around 7.4.

Do bigger water changes every week, eg: 75% water change and gravel clean the substrate every week. Make sure any new water is free of chlorine/ chloramine before it's added to the tank.

 

[guppypups]

It's probably pH shock if you have a pH below 7.0.

Mollies need a GH above 250ppm and a pH above 7.0. If you put mollies in acid water they freak out and die really quickly.

Check the pH of your tap water. If your tap water has a pH below 7.0, you will need to raise the pH in the tank if you want to keep the mollies alive. A couple of bits of limestone, dead coral rubble or some shells put in the tank or filter will help raise the pH a bit. Add a few bits and check the pH after a week. If it's still below 7.0 then add some more limestone, shells or dead coral. Continue adding it until the pH sits just around 7.4.

Do bigger water changes every week, eg: 75% water change and gravel clean the substrate every week. Make sure any new water is free of chlorine/ chloramine before it's added to the tank.

The tap water is 200ppm and is supposed to be 7-7.5 pH.
Any idea whats lowering the ph? Would activated carbon in thr filter do that?

 

[Colin_T]

The tap water is 200ppm and is supposed to be 7-7.5 pH.
Any idea whats lowering the ph? Would activated carbon in thr filter do that?

You need to check the GH, KH and pH of the tap water to find out exactly what it is. You can take a glass full of tap water to the local pet shop and get them to test it for you. Write the results down (in numbers) when they do the tests. And ask them what the results are in (eg: ppm, dGH, or something else).

---------------
The pH in the aquarium can drop from waste products producing nitric acid. It is normally neutralised by the carbonate hardness (KH) in the water, but if you run out of KH, the pH can drop rapidly.

If the water company changes their water source it can change the pH. We have this problem in Perth. During winter we get dam water and the pH is well above 7.0. In summer when the dams are low, they use ground water and the pH is usually below 5.0. So we have to check the pH each time we do water changes to make sure they haven't changed the water source.

 

[Essjay]

The pH of freshly run tap water is often different from water that has been allowed to stand. If you have a pH tester, you need to test both water that's straight out of the tap and water that's been allowed to stand overnight.

 

[Salty&Onion]

I agree with above posts. Mollies should be in a very hard water of hardness of 12dGH (ideally 15dGH or more) and a pH of 7.0, if water hardness is below they will start to shimmy, rocking from side to side which is your weird dance.
Tiger barbs should be in groups of 6 or more, 8" pleco is too big for your tank, I am assuming its the common pleco? Common plecos are the most mistreated fish (just like goldfish and bettas) and they get up to 6ft or larger from what I remember and they need a 100 gallon or larger tank depending on dimensions.

 

[guppypups]

You need to check the GH, KH and pH of the tap water to find out exactly what it is. You can take a glass full of tap water to the local pet shop and get them to test it for you. Write the results down (in numbers) when they do the tests. And ask them what the results are in (eg: ppm, dGH, or something else).

---------------
The pH in the aquarium can drop from waste products producing nitric acid. It is normally neutralised by the carbonate hardness (KH) in the water, but if you run out of KH, the pH can drop rapidly.

If the water company changes their water source it can change the pH. We have this problem in Perth. During winter we get dam water and the pH is well above 7.0. In summer when the dams are low, they use ground water and the pH is usually below 5.0. So we have to check the pH each time we do water changes to make sure they haven't changed the water source.

Tap pH is 7
So I don't know what's dropping it
Should I add pH up? I know its temporary and not ideal but it would give time to figure out what's changing the pH

 

[Byron]

Tap pH is 7
So I don't know what's dropping it
Should I add pH up? I know its temporary and not ideal but it would give time to figure out what's changing the pH

No, do not use pH Up. We must know the GH and KH of your source water before we can sort this out for you. The pH is connected to GH and KH. We also need to know the actual pH of the tap water, which you determine by letting a glass of water sit 24 hours then test as essjay explained.

As for the GH and KH, you may be able to find this on your municipal water authority's website, or call them. Make sure you get the number and the unit of measurement they use.

Once we knbow the GH, KH and pH we will be able to explain this. It is not unnatural.

 

[guppypups]

No, do not use pH Up. We must know the GH and KH of your source water before we can sort this out for you. The pH is connected to GH and KH. We also need to know the actual pH of the tap water, which you determine by letting a glass of water sit 24 hours then test as essjay explained.

As for the GH and KH, you may be able to find this on your municipal water authority's website, or call them. Make sure you get the number and the unit of measurement they use.

Once we knbow the GH, KH and pH we will be able to explain this. It is not unnatural.

According to the water quality sheet for North Calgary (where I live):
pH: 7.1-8, averaging 7.6
GH: 10.9-13.2 grains per gallon, averaging 12.1
KH: 174-267, averaging 214 mg/L as CaCO3

I never knew there was so much to know about water affecting fish! I'm still relatively new to the hobby and I only ever seem to discover this kind of stuff when something goes wrong

 

[Byron]

According to the water quality sheet for North Calgary (where I live):
pH: 7.1-8, averaging 7.6
GH: 10.9-13.2 grains per gallon, averaging 12.1
KH: 174-267, averaging 214 mg/L as CaCO3

I never knew there was so much to know about water affecting fish! I'm still relatively new to the hobby and I only ever seem to discover this kind of stuff when something goes wrong

That converts to roughly 200 ppm (12 gpg) or 11 dGH. The KH is comparable. So this should buffer the pH fairly well, meaning it will tend to remain close to the pH of the source water at the time you add it. If this varies, that is something else. But I woldnot expect to see much lowering in the aquarium with this GH and KH.

 

[Colin_T]

do a 50% water change on the tank and see if it helps.