fish has red spot

Mr Pinchers

after a long period of time with fish dying we finally have the tank stabalized. its been almost a year now and no fatalities. i have 3 danios, 2 cherry barbs, 1 checkered bard, 1 bushy nosed pleco and 1 horse face loach.

just today though i noticed one of the danios has a red spot slightly behind his one side fin (its not a red gill). it looks like the scales have been rubbed off. i feed them a variaty of foods. pelets, algea/sinking waffers, freeze dried tubifex worms and for the last 2 months i fed them live blood worms. the bloodworms were for my beta which suddenly refused to eat anything but live worms but since there were so many the guy at the pet store suggested to also feed the main tank, which i have. i checked the PH and it was slightly high but all the other fish look fine. i added some PH up and a little aquarium salt.

anyone have any advice? to my knoledge the fish have never been aggressive with eatch other so i'm doubtful its a attack wound.

FDStation152

Um you tested the pH as being high and you added ph UP? Use caution with those pH adjusters because once they overcome the buffering capacity of your water the pH with change drastically in a short period of time. You may want to observe the fish and make sure its not some sort of injury caused by another fish picking on him.

Lupin

Welcome.

What are your water parameters? Ammonia, nitrites and nitrates. I would stop the use of pH chemicals such as pH up. They do nothing but harm your fish. Once the effects worn off, the pH will shift back to its usual level. Such shifts can greatly harm your fish.

What live worms were you using?

Mr Pinchers

i ment it was low and added PH up

its just we had ALOT of low PH problems in the past and things like that were the only things that helped.

i don't have any nitrogen strips to test but PH was about 6.2, ammonia is high right now about 6.0. but i had just tested it prior, about 2 weeks ago and it was almost zero.

i'm thinking of doing a water change tommarow.

the live worms are blood worms

Lupin

Use crushed oyster shells to increase the pH.

FDStation152

wow thats a high ammonia reading. suprised anything is holding on in there. the tank definitely isn't stable if the ammonia is spiking like that. did you change out the filter media recently or anything like that? that or you're overfeeding by quite a bit. decaying food will spike the ammonia too.

Mr Pinchers

well i just did a small water change at the moment to help with the ammonia. i'm not feeding them any more then i usually do. the last filter i changed was about 2 weeks ago. it was a mechanical filter. acually i've had the ammonia up alot higher in the past but that was with cycling. it hasn't spiked like this for months.

how often should you feed a 20 gal tank with 10 fish(forgot my 2 corys)? i usually give them about 10 pellets a day along with 1/2 alge wafer or 1/2 tubifex cube. its always gone by morning. usuallyi'll skip a day here and there as well.

crushed oyster shells increase PH? any particular brand or anything like that? how much would one put in a 20 gal? and is there anything you should use to stabalize PH when you get it to the right level?

thanks for the replys btw. i appricate the input

FDStation152

fish really shouldn't be fed more than they'll eat in a minute or two...overfeeding is probably causing the ammonia spikes.

musho3210

never, i repeat, never add chemicals to raise or lower ph, it is dangerous, costs quite a lot, and is even worse than having a bad ph in the first place.

The reason of this is because the chemical only lasts for a very short time. An example is

Current ph 6.5
Wanted ph 7.5
You add ph plus
your ph is now 7.5
Two days later it is back to 6.5
your fish are now dead.

It is a high swing of ph, from 6.5 to 7.5 immediatly, and from 7.5 to 6.5 immediatly, within 48 hours. Fish can adapt to a wide varriety of ph so let them adapt to it.

FDStation152

well I wouldn't say never but generally speaking its a very bad idea for the reasons musho stated. the only exception to that in my opinion would be their use in an extreme emergency (severe pH crash, etc) were the current readings are well beyond the limits of you fish to survive in which case the massive pH swing would be better than letting the fish continue under the current pH. It might kill the fish anyway but gives them a better chance at survival.