Sudden loss of half of our fish, FW... nitrate, nutritional deficiency effects likely   9/27/07 Hi, We're (my 9-yr-old daughter & I) fairly new to the land of tropical fish keeping (we started in January); I've read your website a lot and have learned so much, and we wrote you a while back about a sick fish. All had been going well with our aquarium for a couple of months, then in the last few days we had 5 fish die. We are so sad. I'm hoping that if I describe the situation, you might have some insight as to what happened/what we can do to keep the remaining fish alive. I'd gotten some ideas from your website but I'm really not sure what to think of all this. We have a 12-gallon Eclipse system that has been cycled since last January (we did fish-less cycling ?worked great), and we've had a few different inhabitants along the way but we'd been stable for the past 3 months or so with: 5 Platies, 3 Danios (2 zebra, 1 leopard), 2 Otocinclus, 2 panda cories. The tank has one Amazon sword plant that is not robust but sends out new baby leaves and hangs on. We do 25% water changes every 2 weeks; though we've only been siphoning the gravel once a month, the other time we just change out the water). <Mmm... a dangerous, too-changeable approach... Best to make more frequent, smaller change-outs. Please read here: http://www.wetwebmedia.com/FWSubWebIndex/fwh2ochgs.htm and the linked files above> We feed with a tropical fish flake food, <Mmm, may want to mix in some more substantial fare... frozen or dried, freeze-dried foods...> and once a week or so an algae tablet. We had ended up with not an ideal male/female ratio with the Platies, 2 females and 3 males, and our oldest male (a 1 ½ inch Mickey Mouse) was rather an alpha male when we added his 4 friends, he chased everyone, but after a couple weeks they all seemed to get along with minimal chasing. A couple weeks ago, the Platies starting dying, one by one; we have only one left (the Mickey Mouse). The Platies showed no sign of illness that we could see (spots, growths), but, each time a couple days before they died, they stopped eating. They would try to eat, but spit it out. Then they would start swimming with fins clamped. They would lose that nice round platy shape, and die. In the middle of this, one of the zebra Danios got a really fat belly all of a sudden and the next day it was dead. <Yikes> So, once this started happening, we did a water change <How much and how?> and started looking on your site. We have a test kit, our measurements were: Ammonia 0, Nitrite 0, Nitrate 40. <Much too high... You want to keep NO3 under 20 ppm> Temp is 78. One other idea I saw was malnutrition ? <Yes> so I bought some frozen Emerald Entree which has veggies in it as I thought it possible they weren't getting enough veggies. <Or protein> I put an algae tablet in too, and the Platies did go after that. They didn't much go for the Emerald Entree. Another idea I saw was internal parasites, but as nothing new had been introduced in the tank I hated to just medicate without some more of an idea of what it might be? <Good> I did add 1/8 tsp. salt which isn't much but I read that the cories don't tolerate salt well. <Correct> So, we're very sad and I'm thinking we should've done something else but I don't know what. From this description, can you offer an idea of what we might do at this point? <The nitrate, nutritional deficiency effects likely...> The Mickey Mouse platy is looking very sad on his own, and the 2 remaining Danios are wildly chasing each other around ? I know we should not introduce any new fish until we are stable again but we sure would like to not lose these guys too. The Oto's seem fine, they are a bit skittish but they always have been. The panda cories are extremely shy, they will not come out if we are nearby and I only get a glimpse of them every once in a while (like when we do a water change and move the furniture to siphon) and they seem OK. Any ideas you have would be appreciated. Thanks, Jana (and Jenny) <Bob Fenner>
Re: sudden loss of half of our fish... FW cycling    9/28/07 Thanks for your reply. We now have 2 different kinds of flake food, some TetraMin crisps for tropical fish, the frozen emerald entree, frozen brine shrimp, and the algae pellets. I hope a combination of these foods will be better nutritionally for our fish. If you have any other suggestions they are welcome. <Posted...> We will also start doing 2-2.5 gallon (17-20%) water changes once a week. <Good> How long do you recommend we wait before adding new fish? <At least two weeks> And, I know you recommend a quarantine tank; we have a 6 gallon Eclipse system that a neighbor gave us when they moved, however it is currently dry except the BioWheel has been kept in a jar of water and fed a couple drops of ammonia every 2-3 days. But I have no idea if the good bacteria would still be around on the wheel -- is there a way to keep a BioWheel "alive" if we can't keep the tank set up all the time? <Mmm, well... they're "in the air"... will get there in time...> That is a side question -- the main question is, if we set this tank up with some gravel and water (how much water?) <A gallon or two> from our current tank and put the BioWheel in, are we likely to have a cycled tank 'soon', or will we have to start from scratch with our fish-less cycling schedule? <Siphon some gunk out of the present tank, place it in the new... Will likely instantly cycle> We have a test kit so I can monitor for ammonia, nitrite, nitrate... Thanks, Jana <Read on my friend... http://www.wetwebmedia.com/FWSubWebIndex/fwestcycling.htm Bob Fenner>