[dinthbrgh]

A couple of you have helped me through a serious case of Columnaris a couple of months ago that I am beginning to think may have been the result of adding what I suspect were wild caught Cardinal Tetras to my 75g without qt. Shame on me!

I remember what you told me, Colin, about your Boesemanis eating a whole tank full of them once...(i'm thinking it may have been a case of wild rainbows who were conditioned to hunt their food; and I'm hoping tank-raised rainbows, who get food handed to them, won't have the same tendencies). Never-the-less, I'm still hoping to add a school of Cardinals to my 75. I still have the one survivor from the "incident" in there all by himself; he seems fine;no one bothers him.

So, I started building a new school about a month or so ago in the 30g I set up just for qt. I was buying from the same store I bought the original 10 from because they were the only store carrying them. In small chunks (5 here, 7 there, lost one here, lost another one there) I had 10 that had been doing pretty well for about 2 1/2 weeks, when I bought another 11. Fish started dying. within 3 days I had lost 12, and by the end of the next night I had lost all but 4. Good thing they were in qt! I have no idea what killed them. They showed no symptoms. So, I have left this remaining 4 in there for the past 2 weeks and they're fine.

Rather than treat the 30g I'm thinking I'll move them into the 10g and tear the 30 down now. There is another lfs (my favorite and probably the best locally) that has finally bred Cardinals and is now offering tank-raised Cardinals. I thought I could pick up maybe 5 of these tank raised fish and put them in the 10g with the 4 survivors and if no one died I could expect that these survivors are safe. That is actually a question. If not, I can treat them in the 10g and then build a school in there. Sound sane?

[mikev]

Sounds like a plan.

I'd not mix 4" fish with 1" fish unless you have good reasons to think this is safe.... wild caught or tank raised, the difference in sizes is such that smaller fish looks like food.
Cardinal tetras can be kept in a tanks smaller than 75g.... What you want for 75g would be more rainbows,...just get them from a breeder or quarantine them to avoid another infection.

[dinthbrgh]

I'm up to about 65" in fish (adult size) if the Boesemanis get to 5". How high can I safely go? How close do I need to stay to the 1 inch rule? Not sure, but I think I'd like a couple more Boesemanis in there. I just don't want it to get too crowded. I've seen tanks like that and it makes my head spin.

I have considered keeping the 30g and moving the Lemon Tetras into there and adding some other rainbows.

I also saw these fish at one lfs a while back...he called them Red Velvet Swords but when I researched online the only thing I could find that looked like them was listed as Longfin Red Eye Swords. They were really beautiful but he only got in 4 and they didn't survive the shipping. Dead within a week. Does anyone know about these, or a good breeder of them? I think I might like to try to breed these. An easy start into the world of breeding.

Not sure yet, but I want to think it through before I make any decisions and end up with fish I don't really want. I'm still considering Marks Pagais as well. I know I would love those!

[killiguy]

Ive kept Cardinals for years and they are my favourite dither fish for Apitso Cichlids and other black waterfish.They are a great breeding challenge as well.I have had very few problems with them when they are in pH about or less than 6.0 and down to 4.0 or so.I have had anchor worms on a few batches but no other problems and have had batches live for 3-4 years
.
I would have thought that the water needed for Boesmanis and Cardinals would be opposite ends of the spectrum.What water are you trying to keep the fish in??Cardinals are very prone to bacterial disease when in higher pH water (the very water Boesis like)and that may explain some of your problems

[mikev]

Per previous post, it is 7.6-8.0

[killiguy]

I didnt wade through that last post but cardinals will never do well at that pH level.
Id return them or create a separate tank with a soft acid theme.

[dinthbrgh]

I really do love the look of them, but I can't imagine being able to do anything that will bring my ph down naturally and I have, essentially, liquid rock for water.
I read these websites that say most fish can adapt to just about any water, and if the fish are born and raised in local water they adapt to it, so I thought I had a good chance of accomplishing my goal of a large school of Cardinals.
I have an artists spirit, so to me a fishtank is like a blank page and I have a big box of crayons! I can paint it with any living, moving color I want. So it's all about the mix of color, shape and size. It was all about what I wanted. Now you're telling me I gotta think about what the fish want? Dang!

[Colin_T]

Cardinal tetras are generally captive bred in Asia. If they are wild caught they will be labelled as such at the shop.

If you grow up young rainbows with tetras, they will be less inclined to eat them when they get older. A similar thing happens with freshwater angelfish. Everyone wants a tank with angels and neons. So they buy some angels and put some neons in with them. If the angelfish are small when the neons are introduced, there is usually no problem. However, if you add some neons to a tank containing large angelfish, the neons usually get eaten. If it’s small and wriggly and fits in the mouth, it gets eaten. If they grow up with them, they are less likely to eat them when bigger.

When you have fish in a quarantine tank you should not add any new fish until the original occupants have been moved out. Unfortunately by adding new fish to the tank you introduced another disease, which has subsequently killed the healthy specimens that were there previously.
If you want a group of Cardinal or Neon tetras, either buy a group of 20 initially and quarantine them all at the same time. Or buy a group of 5 or 6, quarantine them and if they are fine after a month, then add them to the display tank. Then go and get some more that can go into the quarantine tank.
I should have actually put this in the thread about Q tanks and I will shortly. Sorry about that. If I had you might still have a few more Cardinals.

A 10gallon tank is ample for quarantining most fishes that are less than 5inches long.

Most fishes can adjust to different water chemistry, be it hard & alkaline or soft & acid water. And whilst M. boesemani do come from hard alkaline water, captive bred tetras will usually do fine in it too as long as it isn’t extreme. A pH of 7.6-7.8 should not be a problem for most species of captive bred fish.
The main issue associated with high pH is ammonia. It becomes more toxic as the pH goes up above 7.0, the higher the pH the more toxic it becomes. Therefore you must have better filtration to compensate for its toxicity at the higher pH. Any filter that can turn over the tank volume 4 or 5 times per hour should be adequate.
_________________
Kicked a black cat? Sounds more like ran over one, backed over it, hunted down its mother and did the same

[killiguy]

[dinthbrgh]

What, physically, differentiates soft-water and hard-water fish? Are their gills different? Skin? Internal organs function differently? If a hard-water fish is born in soft water, (or vice-versa) why is life so much harder for them? Just curious.

[Colin_T]

[mikev]

Brief explanation: Unlike us, a fish exists in an open system, water and ions may pass through the skin and gills. In order to stay alive, a fish must maintain constant osmolarity, gills and kidneys are the two main organs that constantly adjust the osmotic pressure. To maintain proper osmolarity, fish may expel excess water or ions. A fish always osmoregulates since the internal pressure never matches the external one exactly, but the load of work it needs to do differs.

Most species are designed to osmoregulate only within a specific range. Some (salmon, and perhaps some rainbows, like sigs) can handle very wide ranges (soft fresh all the way to sea water!), but these are in minority. Many species can handle osmotic pressure outside of the allowed range for extended period of time, but this will usually result in faster wear; for instance, overuse of kidneys may result in a kidney failure that would manifest itself as a bloat death. In other cases, you should see a reduced lifespan. In yet other cases you should see much greater susceptibility to diseases (the animal is under a constant stress), Lori's recent example of Celebes Rainbows in soft and hard water may be an illustration here.

Wiki

I do not think we really have data in most of the cases; it can only be obtained by measuring lifespans of genetically identical fish in different water... large scale experiments which were not done. Given that we don't really know the specifics of each case, IMHO one simply should not place any animal that evolved in one environment into a drastically different one.

hth

This is a bit off topic, but intriguing: what is the original function of gills?. Perhaps Ion exchange is more important than oxygen?

[dinthbrgh]

[Colin_T]

[mikev]

D,

this is worth understanding...osmoregulation is behind many different things that happens in aquaria. Google for "osmoregulation in fish", perhaps you can find some clearer explanation (I could not, Wiki seems as clear as they get).