20 Gallon Tank Betta Fish Has Grown Pale and Lethargic After Water Change.

I've got an imgur album attached here.

Tank
What is the water volume of the tank?
20 Gallons.

How long has the tank been running?
Roughly 4 months.

Does it have a filter?
Yes -- A sponge filter and the one it came with.

Does it have a heater?
Yes.

What is the water temperature?
Roughly 78 degrees Farenheit.

What is the entire stocking of this tank? (Please list all fish and inverts.)

1 Betta Fish, a few pest snails -- roughly 5?

Maintenance
How often do you change the water?
Weekly.

How much of the water do you change?
Roughly 20%

What do you use to treat your water?
Nutrafin Aqua Plus

Do you vacuum the substrate or just the water?
I try to vacuum the substrate.

*Parameters - Very Important
Did you cycle your tank before adding fish?
Yes

What do you use to test the water?
API Freshwater Master Test Kit

What are your parameters? We need to know the exact numbers, not just “fine” or “safe”.
Ammonia: ~0
Nitrite: ~0
Nitrate: ~20
pH: ~7.2

Feeding
How often do you feed your fish?
Once a day

How much do you feed your fish?
He typically gets either 2-3 betta pellets, a betta bite flake, a small pinch of a crushed up freeze dried brine shrimp cube, or 1-2 freeze dried bloodworms depending on the day.

What brand of food do you feed your fish?
Hikari Pellets, Omega One Bloodworms + Brine Shrimp, Fluval Bug Bites

Do you feed frozen or freeze-dried foods?
Yes.

Illness & Symptoms
How long have you had this fish?
Roughly 3 months

How long ago did you first notice these symptoms?
Around five days ago.

In a few words, can you explain the symptoms?

He's went from an active betta to lethargic. He's often resting on the bottom of his tank, and will only swim for food. He can swim, and does so in bursts of energy -- before falling back down to the bottom and sometimes even falling onto his side.

Have you started any treatment for the illness?
No, I'm too scared to potentially guess wrong and make it worse. I've never treated a sick betta before.

Was your fish physically ill or injured upon purchase?
Potentially, yes. He was very small, weak and pale upon purchase.

How has its behavior and appearance changed, if at all?
He used to be quite lively and energetic; now he spends most of his days at the bottom of the tank, resting. He only swims for food, and does so in his old lively manner, but loses stamina easily and falls back down to the ground.

Explain your emergency situation in detail. (Please give a clear explanation of what is going on, include details from the beginning of the illness leading up to now)

At first, I thought it was due to my poor eyesight -- I wouldn't see him swimming and go looking for him, only for him to pop up from behind a plant or the ground. It'd eventually progress into him staying on the ground for longer and longer periods of time -- now he sometimes doesn't even go up for food unless I show him where it is.

 

Could you get a top view picture so that we can check for pine coning? You could try soaking pellets in garlic guard or garlic juice to try and tempt his appetite, he does appear to be thin.

 

Top-down photo has been added! He'll swim for food, and his appetite hasn't really changed very much; the feeding troubles so far mainly stems from him not noticing there is food, or not having the energy to swim up to it if he's being particularly active (he takes a short break before trying again.)

Could you get a top view picture so that we can check for pine coning? You could try soaking pellets in garlic guard or garlic juice to try and tempt his appetite, he does appear to be thin.

I don't really think he's pineconing; but I've never treated a sick betta before, and am generally new to this overall.

 

Top-down photo has been added! He'll swim for food, and his appetite hasn't really changed very much; the feeding troubles so far mainly stems from him not noticing there is food, or not having the energy to swim up to it if he's being particularly active (he takes a short break before trying again.)


I don't really think he's pineconing; but I've never treated a sick betta before, and am generally new to this overall.

Maybe try putting him in a breeder box or lowering the water level to make it a little easier? Honestly, it isn’t easy to tell what is wrong with him. Hopefully a little fattening up will improve his condition, maybe increase food to twice a day? If he isn’t gaining weight within the week, you might be dealing with an internal parasite.

 

Maybe try putting him in a breeder box or lowering the water level to make it a little easier? Honestly, it isn’t easy to tell what is wrong with him. Hopefully a little fattening up will improve his condition, maybe increase food to twice a day? If he isn’t gaining weight within the week, you might be dealing with an internal parasite.

Alright, thank you! I think? it may be a case of fin rot -- but I'm not very experienced at all in this area; current plan is to add some stress guard, swap the conditioner to prime, and up the water changes as well on top of your recommendations.

 

It seems the little guy is running out of energy. Some juicy treats may help with that. If he has a betta hammock he could stay a bit closer to the surface, making it less work to come up for air, or get fed.

 

It seems the little guy is running out of energy. Some juicy treats may help with that. If he has a betta hammock he could stay a bit closer to the surface, making it less work to come up for air, or get fed.

Thank you! He does have a hammock, and a betta log; he used them lots prior to growing super lethargic, but now he prefers to lie underneath his driftwood until he spots food :c I have upped his feedings to twice a day to hopefully gain some weight back on him.

 

Alright, thank you! I think? it may be a case of fin rot -- but I'm not very experienced at all in this area; current plan is to add some stress guard, swap the conditioner to prime, and up the water changes as well on top of your recommendations.

To me, it looks like he has some tears in the fins rather than actual rot. Either way, your plan should help.

 

To me, it looks like he has some tears in the fins rather than actual rot. Either way, your plan should help.

Alright then, thank you! I went with fin rot as another person suggested it to me, and I did notice some damage on his fins. If it's not fin rot, I really don't know what it could be -- I've never had a betta grow so lethargic so fast -- but it is reassuring to hear that my plan should aid him.