Dainty Cories and CPDs occasionally swimming erratically and flashing

[missmonday]

Hi all,

This one kinda has me at a loss. There are 8 CPDs and 10 dainty cories in my 20g long kept at 75F with 2 filters (fluval c2 and a sponge filter).

It had primarily just been the dainty cories (usually only one at a time) that would swim strangely, then do "backflips" to scratch against the substrate. I noticed my CPDs doing the same thing and got worried...

I'm already on the 2nd dose of prazipro because I don't see anything external like ich or velvet. It almost looks like a fish seizure comes before the flashing.

Any advice? Everyone is still eating and I haven't had any deaths. This behavior only happens occasionally, but it concerns me :/

I have plants, shrimp, and driftwood and rocks inthe tank, but they only scratch against the sand.

 

[Delapool]

Had you added anything recently? Even if it was a filter change with new filter pad / wool.

 

[missmonday]

Well, about a week or so (don't actually remember the day) I had added a small ceramic cichlid cave and small one or two inch pieces of Indian almond leaf to the tank. I only added two pieces of the IAL, hopefully to counterbalance the crushed coral I've had to put in my tank because my local tap has no kh buffer. The pH is higher than I'd like, so I've been ever so gradually removing some of the crushed coral from a little mesh media bag in my filter with every water change.

I have been sort of off-and-on adding melafix (I know it's not very effective) because one of my cories had a sort of white scar-looking spot, I didn't know if it was fungus or not. It's not fuzzy at all, no red ring around it, hasn't gotten any bigger or smaller and the cory in particular isn't lethargic or anything. It could just be natural coloring and I'm being overly paranoid! That was the reason why I was using melafix to see if it would help one way or the other because it's so mild. By off and on I mean not everyday, maybe every two days...or whenever I remembered heh (full time university student with a 20hr a week part time job).

The "whenever I remembered" schedule is also what kinda happens with my plant fertilizers. I only dose seachem flourish (after pwcs, but I'm cautious because of my cherry shrimp) and flourish excel. I've been dosing these two the whole time and it doesn't seem to bother the fish, shrimp, etc.

Last time I checked my water params it was 0/0/5, so water quality isn't an issue. Another thing is from what I typically understand about "flashing" behavior or fish-related illness/stress, they'll crash into anything. But these guys only seem to want to occasionally rub against my sand. It's just generic petco black sand. The cories have no problem sifting through it and I have some MTS so it'll help mix it up too. The behavior isn't all the time either, it's not very often at all it just seems so random...

I'll do another dose of prazipro after this one is up because you never know. My first thought was gill flukes maybe? Generally speaking, the fish don't seem to be breathing rapidly or at the surface though, so it's just a guess. The tank is cycled, obviously, but it's only about a month old (not from initial set up, but from being cycled). Sorry for the novel!!

 

[Matt68005]

I have been sort of off-and-on adding melafix (I know it's not very effective)

Absolutely useless product. You cant "clean up" the bacteria on a fish, in a fishtank full of bacteria. Its impossible, and does more harm than good.
Would be better off in a hospital tank/tub or a small container with some Methylene Blue.
Flashing can be a number of problems, the occasional flash is just them scratching, but if they do it alot....
I would do a large water change and observe if they seem to get better. If they keep flashing i would put some Rid Ick in the tank and go from there.
Prazipro was a good choice tho, fish with gill flukes have a open mouth and trouble breathing, as well as flashing.
Their mouths look "stuck open" a little bit.