A Sad Little Green Tiger Barb

Argh!!!!! White spots on the guppy, that'll be the problem!!!  I'm on my way to the LFS now to get some treatment!!

Argh!!!!! White spots on the guppy, that'll be the problem!!!  I'm on my way to the LFS now to get some treatment!!

That could well be making the fish off-colour.

Because of the nature of the whitespot parasite you'll need to follow the instructions on the bottle to the letter. The parasite has three stages to its lifecycle and it can only be killed in one of them. The first stage is attached to the fish where it eats the fish's tissues - this is what we see as the spots. They have a coating round them so the medication can't get to them. When they've eaten enough, they fall off - stage 2. They sit on the bottom of the tank inside the coating and multiply - and again, the med can't get to them. Stage 3 is when the cysts split open and the tiny parasites go looking for a fish to infect. This free swimming stage is the only one where it can be killed. When a tank has whitespot there will be parasites in all three stages, and there must be some med still in the water when every last one gets to stage 3.
Turning the heater up to ~30^oC will make the parasite go through its lifecycle faster so it will be killed faster

That nice new carbon you've just bought - have you put it in the tank yet? I ask because it will remove the medication so if you've put some in, you'll need to take it back out before treating. If you haven't used it yet save it till the whitespot has gone and use it to remove the medication.
What exactly do you have in your filter? I assume you have carbon as you've just bought more, but what else is in there? Sponge? Ceramics?



The only problem you may have is if you find ammonia when you test as you will need to do water changes. If there is ammonia, you'll need to do as big a water change as necessary to dilute it to virtually zero - certainly to well below 0.25. And the same for nitrite if you get a reading for that.
The way to do the water changes while also treating for whitespot:

• do a big water change and gravel clean before adding the first dose. That will remove a lot of the cysts (stage 2) off the bottom of the tank.
• most whitespot med are dosed on certain days with gaps between. If it's a dosing day, do the water change then add the full dose
• if it's not a dosing day, do a water change and add the amount of medication for the volume of new water only

So your filter just had carbon 

What make is it, I'll see if I can find the manual.
I despair of some filters being made nowadays. I just can't understand why they have media that has to be replaced, throwing away all the bacteria every time. Such filters can never be cycled without some drastic changes to the media.

Make sure you turn the temperature up as well as adding the medicaition. Sometimes the dosing regime is too short if you leave the temp at 25-ish. It needs to be around 30 to speed up the whitespot's lifecycle. As it's only temporary the fish will be OK. But make sure the filter outflow is rippling the surface well. The warmer the water the less oxygen it can hold, and in addition, some meds remove oxygen so you need to make sure plenty is getting into the water.
The problem with whitespot is that even though it has gone from the fish, it won't all be dead yet. Keep on treating even if there are no spots left on the fish.

If you see ammonia or nitrite when you test (which you should be doing twice a day) you'll have to do a water change to get them down well below 0.25. Do it just before you add the med.

Well in the time it's taken me to the write the last post we've had a fatality!!! My little ASBO guppy has been found at the bottom of the tank upside down. I tried moving him about in the net a little but he's definitely a goner!! (I hope so anyway cos he's down the toilet now)

Fingers crossed for the platy now, hope he makes it through the next few days.

I've got to break the news to my three year old daughter in the morning!

Sorry to hear about the guppy. It sounds as though there were more problems than just the whitespot. A lot of experienced fishkeepers will not keep guppies because of them dying, an all too common problem nowadays. Yours could well have been one of these weaker fish.

If one fish had whitespot, the whole tank is infected so you need to continue the treatment. The half of the old carbon filter still in the filter, in theory, will remove the med but in pratice if it's been there more than a couple of weeks it should be 'full' and not remove any med.
Because all you have in the filter is half the old carbon filter and half a new sponge, you need to be very careful about what you do next. The remains of the carbon media will contain half the bacteria you had. But you now only have half the fish you had, so that should be enough bacteria. Don't touch the remaining part of the carbon media. You need to wait until you've grown some bacteria in the new sponge before you touch the carbon. That will take at least 4 weeks, maybe six.
Leave the filter alone (apart from a light clean in old tank water that you take out during a water change). In a couple of months, take out the last bit of carbon media and put more sponge in its place. Then you'll have just 2 bits of sponge, which is good.
Forget what I said about using some new carbon to get rid of the med when the treatment is over - that's only for when you have some other mature media in the filter which you don't have. You can remove the med by doing more water changes - you'll be doing those anyway if you find any ammonia or nitrite in the water.

I've googled your filter but the manufacturer's website doesn't appear to have the manuals. (Some do have manuals available as downloads, which is very useful for someone like me to find out about other people's filters    )

Good to hear about the platy.

You don't actually need carbon in a filter full time. I haven't used any for years, not since I discovered I don't need it. So once the new bit of sponge has grown some bacteria, in a couple of months replace the last bit of carbon with more sponge. Sponge only needs changing when it literally falls apart.
I have a very small cheap filter that spends most of its time in the cupboard. I put a bag of carbon in it if I ever need to use it rather than try to squash the carbon in my main filter 

Keep an eye on your ammonia and nitrite now that you've taken half the old filter media out. If you see either of them, do a water change. If you don't, yes leave it till the middle of next week. Once you are sure the whitespot is gone (no sign of spots on the platy for a week) then do a big water change - at least 50%, then daily 20% water changes for a week. That will remove the vast majority of the med. Then go back to weekly maintenance water changes. Don't forget to turn the heater back down as well 

Something I should have mentioned before - don't replace the guppy just yet. Wait until you are absolutely sure the whitespot is gone and you've done the water changes to remove the med. The things involved with getting new fish (catching them in the shop tank, being in a bag, being put into different water etc) are stressful enough for a fish without being put into water with medication in and that's a lot warmer than it's used to.

Water levels checked again all seems ok.  Ammonia is at 0, nitrate is 25, nitrite is 0 and all the others are as before.

Platy is doing ok, no white spots. I've added the last dosage of meds today, so i'll give it until next week then I'll do a water change/clean. I've also put the new carbon I bought into a spare filter I have. Should I use this filter to help remove the rest of the meds after I do a water change next week?

Eventually I shall just use bio-filter as the normal filter and then my spare filter with the carbon to remove any impurities I may have to add in the future.

Good stuff. Sorry to hear about your guppy.