# ongoing tailrot



## eskimofever (May 3, 2007)

hello
a while back my fish tank got really filthy. some of the fish got tailrot. i cleaned up the filter and changed the water and gave the fish some medicine and they got better. several days later they got sick again so i gave them more meds.
i have continued to clean the filter and change the water and medicate them when they get sluggish and their fins get ratty. the sickness returns after several days or a week or so.

HOW DO I FIX THIS??
problem since about 3-4 months ago.

Tank size: approx. 30L or 8 gallons.

Water changes: usually 25%, frequency has been pretty irregular (more often) since they've been getting sick.

Fish: 2 dwarf gouramis--both get sick but not always together, recover quite well
3 platys--one is pretty hardy, the second gets sick occasionally, the third is sick a lot
1 pleco--seems fairly content
1 tiny molly--about 3cm long, died this week, got a broken tail (i think?) and died the next day, seemed fairly healthy

Symptoms: sluggish, stay near bottom of tank, tears in tail and sometimes fins

Medication: tablets of tetracycline. one of the platys seemed to get worse with this, but the gouramis would get better. after a water change the platy would get better then a few days later a gourami would get sick again. i tried putting in another dose after changing the water to prevent another wave of sickness but it just slowed the cycle. the fish would always get sick again. i decided the tablets suck.
last week i started using a methylene blue/acriflavine/malachite green medicine, while one of the gouramis and the wussy platy were sick. gourami is better but not great, platy has not improved.


i took out the filter last week when i put in the new meds, and put it back in after a few days. how soon should i be putting it in after medicating? and how soon should i change the water? its all green like cordial.

sorry about the length of the post.


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## emc7 (Jul 23, 2005)

> took out the filter


All the filter? You need to take out the carbon to slow removing the meds, but if you take out all the filter media, you are a going to have an ammonia spike.


> how soon should i change the water


The directions on the meds should help here, always change water before adding another dose and alway treat for the whole recommended time period. Just like with human diseases, if you stop early you will get a drug-resistant illness. Since you most likely removed or killed you tank's biological filter, you need to treat this like a brand new tank and do frequent water changes.


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## eskimofever (May 3, 2007)

yup, i took out the whole filter. woops.

there aren't really directions on the bottle, just says "repeat after three days if necessary."

what's an ammonia spike?

cheers


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## trashion (Aug 24, 2007)

your tank is GREATLY overstocked. you have wayyyy too much fish in an 8 gallon tank, and i'd bet anything that's why there are persistent, recurring problems. just for example's sake: a pleco will get massive, we're talking 2 feet, and should NOT be in that tank!!!!

an ammonia spike is what happens when you remove the "good" bacteria from your tank. these bacteria break down ammonia and prevent it from harming your fish. when you remove that bacteria, the ammonia produced by fish waste is very toxic to your fish and can make them more susceptible to disease.


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## eskimofever (May 3, 2007)

the type of pleco i have won't get bigger than 4" and it's still only 1". but yeah, it's still pretty crowded.

for the first year that the tank was set up, there were hardly ever problems.
gah!


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## emc7 (Jul 23, 2005)

> for the first year that the tank was set up, there were hardly ever problems


 *sigh* this is common when you stock for the size the fish are and not the size they will be. 
How big are the gouramis now? 
If you are going to give a second dose of meds, change at least 50% of water before you do or you risk killing fish with an overdose. The exception is meds with clear labeling that include water change instructions. Even if you are not going to redose, change lots of water after medicating, and change water between meds. 
Whenever you biology is messed up or when your fish are sick, cut back on feeding (maybe once every other day). One drug site said don't feed at all when using antibiotics (no food=no ammonia) since the antibiotics can wipe out the biology (a good reason for a hospital tank). Reread all the stickies on the nitrogen cycle since you may have go through it again, this time with larger, sick fish. 


> HOW DO I FIX THIS??


A long term solution is to get a 30 Gallon (100L+) tank for the fish and use the little one for isolation and medication.


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## eskimofever (May 3, 2007)

how big are the gouramis? almost the same size as they were when we got them: dwarfs, about 7 or 8cm. all the platys were fully grown when we got them. the pleco has only grown slightly.

i did another water change today, took the carbon out, and put in some more meds. right now one of the gouramis is almost perfect and the smallest platy is sluggish. i'll cut down on the feeding.

i'll read about the nitrogen cycle now.

can't do a bigger tank at this point in time.


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## emc7 (Jul 23, 2005)

> got a broken tail


broken tail? like split in the clear part? That could be fin rot, fin erosion from high ammonia, or fin nipping from other fish. 

Your fish haven grown this year and you are not feeding more? If your problems aren't from fish simply outgrowing the tank then you need to look at other possibilities.

Aggression: Do the gouramis chase other fish? do they nip each other and other fish. Do the platy male(s) constantly harass the female(s) who has no place to hide. Hiding at the bottom of the tank with chewed fins is a logical response to aggression and disease can start with an injury. Fish can grow meaner without getting bigger. Treat with more hiding places and removing bullies.

"Old tank syndrome" aka crashing: Do you have gravel? Do you clean it? Have you tested you nitrates or pH lately? When a lot of waste builds up in the gravel or filter of a tank, the nitrates can become stubbornly high (coming quickly back up after a water change) and the pH can drop suddenly which stresses the fish and can erode fins. Changing water brings pH back up, but if the large buildup of waste remain, it can drop again. A lot of veteran fish keepers "break down" a tank once a year. They take out all the ornaments and filter tubes and and scrub them in a sink with a clean brush and wash the gravel in a strainer or with a big micron filtering power filter. If you ask them why, they answer "to keep it from crashing". This is the treatment for "old tank syndrome".

"new tank syndrome": If something damages your biological filtration, you get to do the cycle over again with all the problems that ammonia and nitrite cause. See the stickies.

Filter getting less effective: If your tank is acting overstocked when it wasn't before and the fish didn't get bigger, the filter could be getting smaller. I mean moving less water. Clean all filter tubes, inspect impellers and gaskets and replace any part that looks worn. If you can't fix it, the treatment is the same as for an overstocked tank, more water changes and possibly add more filtration such as a sponge or box filter. If you have any ammonia or nitrite in an established tank (cycle all done) more filter is needed. If you get nitrate over 40 ppm, more water changes are needed. If you can fit more media in your existing filter without slowing the water flow, you should, Sponges are good because you don't need to remove them when you medicate. 

Nutrition: not likely, but if you had been feeding from the same can for 2 years, the fish could be missing some essential vitamin.

Inconsistent water source: Not likely if you've been lax with water changes. Some water companies will sell water that has sudden changes in pH and/or hardness (because they let an idiot add the buffer or more likely they get the water from 2 or 3 sources). If you do a large water change with significantly different water, you fish will be stressed. 

Well-kept fish should almost never get sick. Kudos to you for looking for a "root cause" behind the recurring illness. 

Best of luck. 

Keep an eye out for a bigger tank, anyway. Used ones can go for 10% of retail and have even been found in the trash. I understand a lot of thing cost a lot more Australia than they do here. 

Those little aquarium systems are beautiful, but I don't think anyone knows how well they will hold up long-term.


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## eskimofever (May 3, 2007)

hey thanks! you're very helpful 

gosh i'm not doing any of the maintenance properly, time to get my act together. but i was told how to cycle the water when i first set up the tank, and i recently did a full clean out: rinsed the gravel, scrubbed the filter etc.. i tried to put as much back in as i could of the old water.

broken tail: the molly had a bend in its tail. like on an angle, not curved. it was prefectly healthy the day before so i don't know if maybe a gourami chased it into a wall.

agression: the dead molly was really unexpected because (apart from the pleco) it seemed to be the most content and got along with the others. gouramis have been getting a bit more aggressive but only really towards each other. they don't tear each other to pieces but i think they're stressed so i'll try and sort out some hiding places until i can organise another tank.

thanks again


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