Intro And My Fishy Project - Cora

Quote from: fcmf

As for the fish, try (or maybe not!) feeding them a piece of papaya fruit

I'll try that, cheers! Anything that excites them and is more interesting than flakes

Without intending to repeat myself, try shelled chopped blanched peas, some occupants in my 200l go nuts for them.

Ok, now we're getting somewhere.

Update:

Ammonia: ~0 (I know I shouldn't have let it drop to zero but I've been underdosing on a daily basis)
Nitrites: >2.0
Nitrates: >10 ppm

Today I have dosed with 4ml ammonia. The tank shouldn't eat that in 24 hours!

Great to see the nitrates finally starting to climb!

I can also upload some pics. Here is the imgur link: http://imgur.com/a/iu3p7

Nice tank. 

Be careful about adding too much ammonia. You don't want nitrite getting to 15 ppm or the cycle will stall. Once the nitrite reading reaches the highest colour it could be anything over that level from the highest colour to infinity. Well, not quite infinity but you get the point 

You could try a dilution test, though it will only be approximate. Since 15 is the critical figure and the test kit stops at 5, I would try mixing 1 part tank water with 2 parts tap water. If that shows the highest colour, your nitrite is above 15. Anywhere below the highest colour is OK but be careful.
If it is over 15, you could try more dilutions (eg 1:4 or even 1:9) to find out how much higher than 15 it is. Then do a water change to get it below 15.

You could try a dilution test,

I did that and then promptly did a water change 

We all made mistakes, the point is to learn from them.
Remember also Gold Mollies will be highly inbred to get that colour and therefore are likely to be intrinsically weak. The same is true of most livebearers, one reason why I have avoided them.

By 8pm last night she was dead. The poor thing has always been a free spark, a wild little trouble-causer chasing fishes and being the first to eat - a real fun character - and always came to greet me at the glass.

Unfortunately, she wasn't the only one. The black molly was resting against the heater, reclined, breathing slowly. I couldn't see the white molly.

I removed plants (most of them fake) one by one. In one of them I saw a pakistani loach - dead. I must have been dead for a day or two. As I looked closely at another plant I saw the other loach, nestled deeply into the plants - also dead. I kept taking plants out and put the three dead fish into a bag.

I took everything out, including 60% of the water and replaced it. I saw the white molly, who earlier today had appeared healthy. In fact, he was "waiting" alongside the gold molly as she lay sick on the floor of the tank. I took some pics of this - I'd love to post them here.

The white molly was now clearly sick - listing and ragged.

Unfortunately I had nothing left with which to euthanise the fish, so I had to wait and wait until they passed naturally. It didn't take long. The black molly was removed when she stopped breathing. The white one was removed hours later when he was lying upside down on the floor of the tank, barely breathing. I don't know if the white molly was still alive at this point but I figured even if he was he'd have a quicker passing than being left in the tank to die in the night.

I felt that these mollies had character, especially the crazy gold one! I'll miss them.

As for the cause? There aren't many options. The tank had a 50% water change just last week and the filters were squeezed clean in tank water. I added Seachem Purigen, which was brilliant for the water. I know that Purigen can interact badly with certain slime coats, but the Interpet Dechlorinator I used doesn't have one, only aloe vera, which unless it's amine based isn't a problem. I did use a small amount of Tetra's CrystalWater - which is supposed to be perfectly safe. I know that loaches can be susceptible to certain treatments because of their scales - who knows. There are stories of CrystalWater deoxygenating the water - but I don't think the fish died from lack of oxygen.

The timeline seems to me that one of the loaches died first, perhaps even 2-3 days ago. Unfortunately, even in a 70L tank there's plenty of places for the fish to hide if they want to - and the loaches have often gone missing. Then the other loach died, perhaps 1-2 days ago. Did the same thing afflict the mollies, or did the dead loaches poison the water? Did one of the mollies (probably that bloody gold one) try to nipple a dead loach and catch something?

The only anomaly of which I can think is the CrystalWater. But that's my opinion.

The mollies and loaches are survived by three scissor tails, two cardinals, six penguin tetras and two coolie loaches.

Edited to add: needless to say, I am gutted. These little lives were in my hands, and to see them slowly lose their life over a few hours was horrible. This experience has reminded me why I do not get pets! But, I am not giving up on the fishies. I'm going to make the new home perfect for the survivors.

So sorry to hear what has happened in your tank over the past few days. How awful to be looking through the tanks for the fish, only to find them either already passed or very ill. I don't know what else to say. 

Nothing that I can add to the helpful comments/suggestions already provided, but just to pass on my sincere condolences to you (and again to Sue) for the distress that you (and she) have gone through in your separate situations.