One Wcmm Died From Dropsy - Please Help Me Find The Cause!

[Fuzzball]

Hi guys,

The minnow in question was purchased some time ago with its current shoal - six altogether, and introduced into a tank that had cycled. (for six weeks) I noticed recently that it was starting to become more and more lethargic, and swollen - and realized to my dismay it had dropsy. Its scales were very visibly pineconed (for someone with trypophobia, what a nightmare!) and it finally succumbed this morning.

Now to tank parameters:

It is a long 10g tank with 6 (now 5) WCMM and 6 pygmy cories. To my understanding this was supposed to be a 100% stocked tank, and in hindsight I should have probably kept it simpler but in my naivety I had really wanted a populated tank. This is also a planted tank, with around 30% of the substrate planted with various stems, and another 30% planted with star grass.

I had a good tank initially - the WCMM were introduced first and six weeks later I introduced the pygmies. At the time I had 0 ammonnia, 0 nitrates, 0 nitrates and had a pH of 6.8. This was all measured with the API master test kit.

Now, since adding the pygmies things had started going out of hand - my nitrates and nitrites are still sitting at 0 (confusingly) but my ammonnia readings were up to 0.5ppm. My pH went down to 6.4, and throughout this time my tank maintained a reading of around 27C/82F. (It's summer here) According to http/dataguru.org/misc/aquarium/AmmoniaTox.html, my tank wasn't too toxic, but I started doing a 40% daily water change to try keep the readings down. My cories and the rest of the WCMM seem to be OK, but I'm dreadfully worried that if one of my minnows caught dropsy the others aren't too far off it too.

Just to note, I'm using a sand substrate so when I vacuum I try to skim the highest layer of sand. (But with varying degrees of success.)

So in light of all this, are there any areas of concern beyond the obvious? I'm a pretty new aquarium owner, and this is my first tank since I was a kid (and I'm talking more than 20 years ago) and that was managed by my parents. I am of course open to any criticism because if I've been stupid I probably deserve it.

So far my main points of concern is the following:

* Out of the tap, my water pH is measured at around 8. I try to let it sit sit over night and that drops down to about 7.5 but it's still a bit too high. However I read that it's not really a good idea for beginners to try mess with the pH as it may crash.

* High ammonnia reading is definitely my biggest worry - I can't seem to get it down any lower than 0.2 in the recent weeks.

Thanks in advance for any help rendered!

 

[the_lock_man]

Dropsy is a symptom, not a disease. It could have been brought on by the raised level of ammonia, but it could be caused by other things too. No way of knowing.
 
A couple of things, I would have thought you're not planted enough to see 0ppm nitrate. With the API test, you have to seriously shake the wossname out of bottle no.2, bang it on the table a few times, to ensure that the powder reagent is fully dissolved in the liquid. Also, if your 0.2ppm ammonia might also be where you need to read the test in natural light, not artificial, otherwise it takes on a distinctly green hue.
 
WCMMs are temperate fish, they need their water a good few degrees cooler than where you have it currently (but this is fine for the cories). I'd suggest that as they start to die, you don't replace them, but instead pick something like chilli rasboras instead.

 

[Fuzzball]

I am mostly worried that the other fish will start developing similar symptoms - particularly the cories as I can't observe them due to the fact that they like to hide when I'm close, and only ever come out to feed when I'm a distance away! (Or have been waiting stationary for a long time.)

Furthermore, to be honest I'm not entirely convinced I know exactly what a % planted tank means. All I did to guestimate the numbers I did was from looking top down at the aquarium and estimating how much gravel can be seen. To that note, I do notice that other aquarium readings tend to have a small nitrate reading instead of just 0 - what should I do to possibly improve that? More plants? But as you said I might not have shaken the bottle was not shaken enough - I'll try that later on.

My ammonnia readings tend to be done in the evenings, in white light! So as you say, my readings may be off and I'll test this again in the morning.

As a sidenote, how do you even observe cories if they have dropsy, besides the behaviorial changes? I don't have the pineconing to watch out for in that case

Thanks for the reply!