Setting Up Hospital Tank... So Frustrating...

[JohnHuff]

I have a new 55g tank. I've had it set up for about 6 weeks only, but I'm an experienced pond keeper so I understand the basics about water quality. After setting up my tank and cycling it I've had 2 Dwarf Gouramis ide, 2 Balloon Belly Mollies die in the last 2-3 days and now it looks like 2 of my longest living Tetras are going too.

The DG's had fungus, one of the BBM had mouth rot, the other BBM may have died of natural causes and I don't see anything on the Tetras so far, but they're doing the dreaded thing which usually foreshadows death: swimming in place and hiding behind a rock.

My set up:
55g tank:
1 30g capacity HOB filter
2 DIY moving bed filters on either end (bottles with cut up straws), one powered by a power head and the other by an airpump.
Airpump powering a 48" diffuser under the gravel
5-6 small plants anchored in the gravel
4 water hyacinths rotated weekly from the pond

Fish: (all the fish are small)
2 DG
6 BBM
5 Tetras
1 Rubber lipped Pleco

I test my water frequently and ammonia, nitite and nitrates are 0, akalinity is low. I don't like using salt for some reason, so I only add a very little salt to the tank.

When the first DG developed fungus I bought a 10g tank and small heater and dosed with Pimafix and salt but it died anyway. Ditto the 2nd DG.

A few days ago, the BBM showed the same symptoms, swimming in place and then I saw it had mouth rot, I switched to a 1 gal tank but only filled it ith 0.5 gal water, dosed with Melafix and Pimafix and salt. After the 1st day it seemed to recover because it started showing more signs of life and swimming. I did a 50% water change, added the dechlorinator, Pimafix, Melafix, a teaspoon of salt. And maybe stupidly, I thought it might be hungry and fed it 3 freeze dried bloodworms which it ate. The next day it was dead. I'm not sure but I think the salt might have killed it.

2 of my Tetras are now showing the classic swimming in place syndrome and I'm really depressed about it since they are of my original bunch and I'm much attached to them. I don't want them to die.

Anyway, my questions are:
1) Do I do a daily water change in the hospital tank? If so, how many percent?
2) Do I feed it in the hospital tank?
3) Should I be using salt when I don't really do so in my regular tank?

Any help here is much appreciated. TIA.

 

[slimeneo]

Hi, I'm somewhat of a beginner and I'm not sure if I can help you much, but a few questions are important:
Is your hospital tank cycled? As in, did you move some of the mature filter media from your 55 gal to the filter in the hospital tank?

When you say nitrates are low, that's a bit alarming since it's unlikely that nitrates are ever 0. What kind of test kit are you using: liquid or test strips?

And to answer your questions:

1) If your tank is cycled and you're adding some kind of medication to the hospital tank, you don't need to do daily water changes (unless the medication calls for it), however if it's NOT cycled, you'll likely have to do 50% water change daily... I'm not sure the 1 gal is a great size for a hospital tank since it's so tiny, ammonia and nitrite can build up very quickly. So I'd suggest using the 10gal.
2) If your hospital tank isn't cycled, I wouldn't feed. I think the freeze-dried bloodworms are definitely not the best thing to feed especially when they are sick... they can cause bloating because when they eat the dried worms, they expand in their stomach as the dried worms soak up water. ALWAYS soak the worms in tank water prior to serving them. And if you like to use it as a treat, I'd say no more than once a week. If you really want to feed them, I'd just stick to flake food (and very little of it)
3) I'm not sure about this question... I think it depends on each kind of fish and their tolerance of salt. I believe that scaleless fish are more sensitive to salt (I could be wrong though!) but salt can be helpful in getting rid of parasites. I would say if you're going to use salt, use a little bit (and be sure that the type of fish you have isn't sensitive to salt). Ease the fish into it, don't just dissolve a lot of salt at once and stress the fish.

Anyway, I think (in my opinion) you probably used too many medications at once: pimafix, melafix and salt could probably stress the fish out a lot. I'm sorry I don't know what illness your tetras have But I hope I have helped some!

 

[WILDER]

What is the brand name of the test kit you are using.
What is your tap nitrate reading. As it rare to have a reading of 0
Tank temp.

What type of fish is a BBM.

 

[JohnHuff]

Thanks for the answers.

The water in the hospital tank is not cycled. I don't believe it needs to be cycled since it's just a temporary tank and it doesn't need cycling if it's fresh tap water. AFAIK, your bacteria will not thrive anyway if the water is fresh and there are no waste products for them to feed on.

The reason I ask about water changes is because of the Melafix and Primafix. I don't know if they stay in the water or get used up. If they don't get used up, then after 7 days (the recommended treatment time), there will be a lot of medication left in the water.

Coming from a pond background, it isn't rare to have a nitrate reading of 0, or for that matter an ammonia or nitrite reading of 0 zero either because all the bacteria and the plants need something to munch on. I believe the nitrate reading of 0 is because it's been uptaken(?) by the plants.

Tank temp is 74F.
BBM is balloon belly molly.

 

[DrRob]

Nitrate of 0 in the aquarium setting is generally a sign of an uncycled tank. To be fair, that's exactly what you have in the hospital. Generally I use 10 gallon tanks for hospitals, but that's because I happen to have them lying around. Regular water changes in a small hospital tank are vital, as it'll still develop a build up of fish waste and has no means of dealing with this.

The salt was unlikely to kill the molly, they're semi brackish water fish anyway, although the sudden change may not have been good for it. As a general rule I use water from the main tank mixed 50/50 with fresh for this sort of thing. A bit like a large water change but not a 100% shock.

Personally, I suspect that your tank hasn't cycled fully, which is what is giving you water quality and therefore fungus issues. I run heavily planted tanks and have never seen a 0 nitrate unless the filter has packed in. Test kits are great but they don't pick up the very low level stuff that still bothers the fish. The reason you're getting away with it is you're understocked for a 55 gallon, but a few good sized water changes in the main tank will probably work wonders and I suspect that you're not far off being fully cycled anyway.

 

[JohnHuff]

Thanks for the reply.

In the future, I will try using some main tank water with fresh water as that will no doubt decrease the water difference and shock to the fish. When you change the hospital tank water, what percentage water change do you do? And do you feed the fish in your hospital tank?

It's definitely possible that the water in the tank has fully cycled yet. I used some water from the pond to kick start the biological process, and the straws in the moving bed filters have attained a brownish tinge, but the amount of media in the moving bed filters seems very small to me since I use a massive amount of media for the pond.

Because every fish I've put into the hospital tank has died I decided not to do that for the Tetras. I've been doing a 15-20% change daily since I posted and so far them seem better. Thanks to all for the comments.