Lethargic guppies

[JollySnook]

I have a 6 gallon planted tank--it is 1.5 years old. 5 days ago my 2 guppies (in addition to these two, I also have a nerite snail and a small ghost shrimp--in other words, the tank is not overstocked) became lethargic and are staying near each other close to the surface in the corner of the tank. I thought I had an ammonia/nitrate spike, but water tests are OK--ammonia and nitrite levels are 0, and nitrates at around 10. I performed a 30% water change 4 days ago just when one of them started acting this way, but not only did it not help, the second guppy joined the first now.

They still show interest in eating, but other than that, neither looks well. I am puzzled to no end. Can anyone offer any clues?

 

[StarGirl]

1st I would check your tap water to see if they may have changed anything in that. Did you remember the dechlorinator?

 

[JollySnook]

1st I would check your tap water to see if they may have changed anything in that. Did you remember the dechlorinator?

 

[Broggy]

what is the hardness?

 

[JollySnook]

Thank you for replying!
I did use Prime--I have a system worked out to help me remember .
The only two things that changed in the last two weeks were a new light fixture (advertised as a better growing light), and a new bacopa plant. I wonder if these changes upset the balance, but water tests are good, so I have been racking my brain. The shrimp and the snail are happy, the guppies are the only ones suffering.

 

[StarGirl]

Hmmm the shrimp are usually the most sensitive so I would venture to guess the guppies were just old or something was wrong with them themselves. Guppies now a days are not the hardiest of fish because of overbreeding in farms.

Did you check the tap water for ammonia, Nitrites and Nitrates? What are the pH and GH/KH in your tank?

 

[Skrabbitskrabbit]

Do you have an air stone? They may (possibly) need more oxygen in the water. My fish were treading water at the surface and acting off but the airstone helped

 

[JollySnook]

Update: one of the guppies died yesterday, and the other is still eating, but her behavior did not change much--she is still not well, so I am guessing it's an illness... I have been trying to look for ich and rot, but cannot see any obvious symptoms other than glassy poop, which can be many things.

Thank you for advice, StarGirl and Skrabbitsrabbit

 

[Skrabbitskrabbit]

Sorry to hear! I don’t have much experience with illnesses so hopefully someone else can add some insight to help your other one. By the way, How long have you had the fish?

 

[JollySnook]

The little guy who died yesterday had been with us since last September, we got him at the same time as another female who died about 6 weeks ago. The girl who looks sick now replaced the original girlfriend about 3 weeks ago.

I keep looking at her--there are no spots of any kind, but she is cramping her tail and treading water at the surface, although she did swim deeper yesterday chasing brine shrimp I gave her for dinner.