u/Upset-Passenger4350

Update and help: what is happening to my loaches?

Original post: https://www.reddit.com/r/freshwateraquarium/s/Y8VPkpWhsp

What first seemed to be cute kuhli behavior now feels like a dark omen. I am now experiencing mass tank casualties and am desperate to fix whatever problem this could be. My plants appear to be dying, there is sediment coating/flying around everywhere. Tank is kept at 80f and is heavily planted. I feed using vibra bites and algae wafers

5/14: suspicious death of an adult yoyo loach and mystery snail. Both found at the top of the tank and passed away overnight. All water parameters normal (ph6.8, 0 ammonia/nitrite, 5 nitrates). Did a 20% water change immediately after finding and chalked it up to murder suicide

5/15: added 3 panda corys and 2 albino corys to tank

5/19: Found a dead panda Cory, albino Cory, and juvenile neon tetra. Albino was torn in half and panda was floating at top. Tetra was dead on bottom. Tank parameters still normal (ph.6.8, 10-20 nitrates, 0 ammonia/nitrite) another 20% water change.

5/20. 1 adult neon tetra dies. I go to the aquarium store to have my water tested professionally and discover slightly high phosphates and a ph of 6.6. Nitrates are at 20ppm and 0 ammonia/nitrites.

Recommended to:
add sponge filter and new plant that will help lower phosphates
feed less (they are fat)
Remove dying plants

5/21. 1 juvenile neon tetra dies

After thorough investigation of the surviving fish, it appears as though my betta has holes in her head. She has had a tumor for months that continues to grow on her tail. All the other fish appear to be normal. I took a picture of one albino Corycat that could suggest ich, but when looking at it through the naked eye it looks like 2 shiny spots. I will post pictures in the comments.

I have lost 28% of my tank at this point and wake up every day to a new dead fish. What can I do to stop this nightmare???

u/Upset-Passenger4350 — 2 days ago

what is happening to my loaches?

Parameters:

29 gal tank
Ph 6.8
Nitrites 0
Nitrates 5
Ammonia 0
Temp 79.7 bottom 80.1 top

Tank members:
1 female betta
2 yoyo loaches
3 kuhli loaches
10 neon tetras
5 Pygmy corys
3 panda corys
2 albino corys
1 assassin snail
1 rabbit snail

My kuhlis have been doing this nonstop for almost two weeks- they eat whenever I feed and will sometimes be sitting on the bottom of the tank, but more often than not they are glass surfing the same area of the tank all day long. I woke up this morning and my 2 yoyos are acting strangely and staying in one spot, on the same side the kuhlis are glass surfing. What is going on?

Changes in environment:

I found one of my yo-yos and my mystery snail dead at the top of the tank two days ago and did a 20% water change immediately. They are the first losses in the new tank (upgraded from a 10gal); it’s been established for about 2 months.

I added sand on top of gravel substrate 2 weeks ago

u/Upset-Passenger4350 — 6 days ago