Just when I thought things were going well and I could introduce my new fish that I've had in quarantine 3 weeks into the main tank, I now see a white pimple thing on the caudal fin of one of my older fish! The fin is also bloodied around the white pimple. Can anyone tell me what I should do? My tank is a 30 gallon. I have 2 fish in it now. I just changed 50% of the water and put in Prime, 3 tsp. Jungle pH 7.0 Stabilizer, 10 ml Aquarium Pharaceuticals Stress Zyme, and 6 tablespoons of aquarium salt. The water parameters are: pH 7.0, Ammonia 0, Nitrites under 2.5, but not 0, Nitrates between 0 and 20.

I wonder if dabbing the spot with hydrogen peroxide and treating the area with neosporin would be appropriate.

just a question, did you treat the water with a pH stabilizer with the pH being 7.0? because if you did, you can cause a crash

Hi goldenlady, what is the ph out of your tap?

Also, if you use Prime, you don't need stresszyme

The real problem I see is your nitrites. 0 - 2.5 is the difference between healthy and deadly. Is there any way you can relook at this? There's a massive difference between the 2 so rechecking this is the first thing I would do.

How long has your tank been set up?
What kind of filtration do you have?

When you have ammonia or nitrites present in the water, your fish become stressed thereby lowering the immunity. It's at this time that opportunistic bacteria can take hold. But I would try doing more waterchanges unless of course your nitrite reading was wrong but will wait for you to confirm.

Please post back soon

I should have mentioned the pH out of the tap. It's 8.6 according to the pH testing I've done. Ok about the Prime. I kind of thought I wouldn't need Stress Zyme because of what it said about it being a dechlorinator, but I added it because the bottle said it had "dual action live bacteria" in it. Thanks for confirming that I don't need to add it, too.

My tanks been up since July when I installed a new Eheim 2213 filter. It's funny about the nitrites, because the ammonia can register 0, yet nitrite readings don't register 0.

Since I just changed 50% of the water today, when should I do another change? In a couple of days? I really appreciate your quick response, Tropicana and JenW. I'm quite stressed about this, because I was so looking forward to letting my three fishes get together today.

Is there any way you can get a new test kit for nitrites? It'd concern me that the silly thing didn't register more accurately

I know Eheim are a terrific filter brand - I have 3 myself and one of those include the 2213. The not so good thing about this particular filter is it only turns over 116 gallons per hour so is really only adequate for a 10 gallon tank. I have mine set up with a fluval 404 and eheim 2224 and that just gives me my 10 x gph filtration. There are some terrific hangon filters that do a good job of acting as a second filter and/or backup when needed and the best i've used are the aquaclears. Adding a second filter that turns over roughly 200 gph would help you keep your water better

Just on the spot - how long has it been there? You can try dabbing the area with hydrogen peroxide but if it's bacterial, then this won't do much unfortunately. You would need to treat the underlying problem first. Is there any way you can get a pic of area?

Also, how readily available are antibacterial meds where you live? You could get some medicated food (medigold) from www.goldfishconnection.com and they can express post it to you overnight and start feeding this to your fish but first, let's try and have a better look at this spot, especially as it could be bacterial (and this is where a pic would help enormously)

I have an HOB (hang on back) Eheim Liberty 150, also. Eheim claims it has 150 gph capability and is for tanks up to 35 gallons. Would adding this power filter be enough? I ended up buying Eheims because the aquarium center where I live thought so highly of them. They use the Professional cannisters in their store. I had no idea that the Eheim 2213 wasn't enough. Eheim claims it is supposed to be good for tanks up to 66 gallons. I thought I had more than enough filtration. I am so disappointed.

As for the pimple on my fish's caudal fin: I first noticed it last night. I do have Medi-Gold, so I can begin feeding the fish that. I just changed water last night, and testing today, the pH is 7.0 and Nitrites are at a slight tinge of pink, but not perfectly clear (0).

I can bring the salt level up to .3 today if I need to (1 Tbsp to 1 gallon). I had it at 1 Tbsp to 5 gallons yesterday.

Adding the HOB to your tank will benefit it greatly When we talk about 10 x gph filtration, it's the best possible scenario to ensure the water remains optimal and unfortunately the 2213 has a very low outflow rate. If you have another filter to add then this is a big plus.

See how you go with feeding the medicated food and salting to 0.3% but if you notice the fin getting worse, post back because you may need to include a waterborne antibacterial med also but hopefully it won't be necessary

Ok. I'll test the water tomorrow, and keep up the meds for a few more days.