A ques­tion about par­a­sites and humic acid…

Hello.

I’m new here, obvi­ously; I’ve been lurk­ing here on and off, but I have decided to make an account.

I have a par­a­site prob­lem right now in a 10 gal­lon tank hous­ing two P. anjun­ga­nen­sis and a small shoal of Boraras uroph­thal­moides (pri­mar­ily as “dither fish”). Every­one has been healthy and tank para­me­ters are up to par, but on Sun­day (last week­end) I noticed that one of the boraras had some tiny lesions/​cysts on its body. I exam­ined the other fish, and while the “Paros” seem to be fine, I had to iso­late five of the boraras because they either had obvi­ous sim­i­lar cysts/​lesions or looked like they were devel­op­ing them.

It took a cou­ple of days to iso­late all of them because the last two were very hard to cap­ture (the tank has a very com­plex hard­scape with tan­gles of moss, java fern, and cer­atopteris, plus float­ing plants), but now all are iso­lated in a “hos­pi­tal tank” and I am treat­ing them with a formalin/​malachite med­ica­tion at a reduced strength.

I am not quite cer­tain what these cyst-​like lesions are being caused by, but I am cer­tain that it is a pro­to­zoan par­a­site, because every­thing about the cysts/​lesions matches. Fur­ther­more, one of the boraras died, and prior to its death I removed it from the hos­pi­tal tank (it was the “runt” of the shoal and it had a heavy load of encysted par­a­sites rel­a­tive to the size of the fish) and took a skin scrap­ing to put under the micro­scope. Sure enough, I saw swarms of tiny organ­isms escap­ing from cysts and mov­ing about the slide in loose aggre­ga­tions.

I sus­pect that this prob­lem arose from one of two sources/​events:

1) I live in Ore­gon, near Port­land, and we had a heat wave sweep through over the last two weeks; tem­per­a­tures soared to near 100 deg. F, so I unplugged the heaters on all of my tanks to keep from over­heat­ing the fish. The heat wave then sub­sided, and after it appeared to have gone I plugged the heaters back in, but the water still cooled to roughly 71 – 72 deg. F for a short time. If the par­a­sites were already in the water, this may have reduced the immune activ­ity in the fish just enough for them become infected.

2) I recently (about a week ago) pur­chased some Cer­atopteris pterid­ioides plants from a new aquar­ium shop that opened up very close to my house. The shop is run by a highly rep­utable fel­low who has been active here for quite some time, and there were no fish in the tank with the plants, so I thought noth­ing of quar­an­tine. Given the cur­rent time­line, it seems pos­si­ble (unfor­tun­tately) that I acquired the par­a­sites from these plants.

In either case, I have no guar­an­tee that the tank (cur­rent occu­pants are now three boraras and the two Paros) is parasite-​free. I recently pur­chased a bot­tle of peat extract from a gar­den shop in the hopes of using it to help keep the water con­di­tions I need going, and I decided to refresh my mem­ory about humic acids here:

www​.skep​ti​calaquar​ist​.com/​h​u​m​i​c​-​a​c​i​d​s

This arti­cle men­tions the fol­low­ing in the third para­graph:

“humins affect the cycling and bioavail­abil­ity of chem­i­cal ele­ments; they repress many bac­te­r­ial pop­u­la­tions and affect the zoo­plank­ton: acidic black­wa­ters rich in humic acids have char­ac­ter­is­ti­cally low pop­u­la­tions of bac­te­ria and a depau­per­ate zoo­plank­ton.“

Since com­mon pro­to­zoan fish par­a­sites have a free-​swimming stage that needs to attach to a host (plus another stage that rests on the sub­strate or other solid sur­faces), and one could con­sider the free-​swimming stage zoo­plank­ton (and nei­ther the substrate-​bound stage or the free-​swimming stage are pro­tected by host tis­sues), could these be sus­cep­ti­ble to a reduced pH brought about by addi­tional humic acids?

I could eas­ily bring the pH of the tank down to less than 6.0 over the course of a day or two. I have been extremely busy lately, so I have not been able to closely reg­u­late the water para­me­ters, and the pH is slighly above 6.0 and I do not have as high a tannin/​humic acid con­cen­tra­tion as I would like. The fish would obvi­ously pre­fer this, but it may be a cre­ative way for me to make life dif­fi­cult for any other par­a­sites that may be attached to fish unde­tected or hid­ing else­where.

I decided to ask this ques­tion here because this board is full of peo­ple who have to play around with humic acids by def­i­n­i­tion, and I was won­der­ing if any­one knows if they can inhibit pro­to­zoan par­a­site activ­ity in a tank with fish that pre­fer black­wa­ter con­di­tions anyway.

Yes I agree with you, snails can trans­mit dis­eases, liv­ing in black water hardly snails and other micro-​organisms have it too hard. I have not yet lost no Paros by par­a­sites, rather byre­act­ing and injuries while catch­ing out even though I sev­eral times a week, my own food which also include native fish catch in dif­fer­ent waters. Paros are in good care really tough and more likely to die of old age as from dis­eases.

Now I see it like Helene, my Paros have no co-​inhabitants and I have where I usu­ally Paros seen in the 20 years no major Kankeiten unless they have become really old, then they get some­times ascites bulging eyes, or cur­va­ture of the spine, but in Age we will get the one or the other dis­ease in Paros, it is the same. Oth­er­wise, they really are not sen­si­tive and are more tol­er­ant even in water val­ues, unless you want to breed, then you need one or the other kind of a lit­tle more attention.

helene wrote: I also keep small boraras in some of my parotanks, — mostly boraras mac­u­la­tus, — and I had in one instance a ter­ri­ble out­break of some­thing which maybe resem­bles what you describe. The boraras was infected with lots of small cysts, — I actu­ally thought it was ‘ick’, — and I remem­ber it came after a change in tem­per­a­ture as well.
It was a small tank, — in fact I had one paro in it and 3 boraras. I didnt med­icate at all, mostly because I had no idea how to treat tiny fish like boraras, — I have not a lot of faith in med­ica­tion for so tiny fishes, and I was wor­ried about affect­ing the paro with med­ica­tion.
So I didnt treat, — and I did loose the boraras, — but the paro was totally unaf­fected even the out­break was very bad. The paro sur­vived and lived long after and it didnt affect any other tanks later.
It was not of course ideal not to treat, but this is the only time I have had any expe­ri­ence of this kind involv­ing both paros and boraras. Nor­mally I do not see this kind of sick­ness with any of the species.
The paros can get odinium, this hap­pens now and again, — but other sick­nesses, — it seems very rare.

How inter­est­ing.

I went on a long hik­ing trip not long after mak­ing this thread, which is why I have not replied until now.

I sep­a­rated all of the infected B. uropthal­moides and treated them with the typ­i­cal (at least in the US) formalin/​malachite green solu­tion so often used against pro­to­zoan par­a­sites. All of them made a com­plete recov­ery by the time I left for my hik­ing trip, and when I returned, there was still no sign what­so­ever of the cysts; they were also put into a tank already hous­ing a few Oryzias fry, and none of the fry became infected either.

I wish my micro­scope was the kind with a cam­era, but it is not, and it is also very old (man­u­fac­tured in 1946 – 48). Even with some of the upgrades I have given it, it can­not com­pete with a newer scope. The organ­isms I viewed under the micro­scope were very sim­i­lar to “ich” in appear­ance, and did not have the golden-​brown color asso­ci­ated with dinofla­gel­lates. The cysts on the fish were also much smaller than those of ich; so small that at first I thought that I was see­ing a pis­ci­noo­d­inium (“vel­vet”) infec­tion.

The Paros were not infected, although they did not take kindly to the dis­tur­bances caused by my attempts to cap­ture the boraras. I have moved the rest of the B. uropthal­moides into a dif­fer­ent tank, and I am mov­ing my B brigit­tae into that tank instead. I also bought some more keta­pang leaves before I left and added them to the tank to help restore the cor­rect water con­di­tions.

So far, every­one seems fine. Also, no wor­ries Deepin Peat: I’m fairly new to black­wa­ter fish still (com­pared to the rest of you), so I appre­ci­ate the extra information.