Stop PWC

[Bigge_al]

I was told by three private pet stores to stop doing PWC that this was the cause of my fish deaths. So I am on week 3 without a water change and my fish have stopped dying and my Ammo and Nitrate level are not moving.
Ammo-.25
Nitrates-40
pH-7.4

Is it possible that my PWC was keeping my cycle from completing and causing fish deaths.

 

[LyndaB]

I've never heard of a fish dying from clean water, unless you have heavy metals in your water and you're not using a dechlorinator.

 

[chagoi]

I agree 100 %......with LyndaB

 

[Convict2161]

I'd have to agree as well with the others. You can bring your water to a local pool maintenance company, they may test it for you. They have a sheet of tests they perform right there in there shop.

I'm actually going through this now. I'm bringing the amount they asked for on Monday and there gonna test for everything they can.

 

[aquaponicpaw]

Ammo-.25
Nitrates-40
pH-7.4

Is it possible that my PWC was keeping my cycle from completing and causing fish deaths.

Most certainly! bacteria is the variable. They need "dirty" water to live. no matter if it is fish or fishless cycling. You've got to allow your nitrogen cycle to complete. Sounds like you kept resetting yours. Glad it's on track.

 

[Slade]

Very few bacteria are in the water itself. They grow in the filter and on rocks & gravel. Something is off in your tap water: ammonia, ph, nitrite, nitrate, temperature or not dechlorinating. I suggest testing tap water and compare to tank readings.
How many fish are you cycling with, and what is your filtration?

 

[Bigge_al]

I have been up and running for 2 months. I have 2-40g filters with close to 20 fish.

 

[aquaponicpaw]

Very few bacteria are in the water itself. They grow in the filter and on rocks & gravel. Something is off in your tap water: ammonia, ph, nitrite, nitrate, temperature or not dechlorinating. I suggest testing tap water and compare to tank readings.
How many fish are you cycling with, and what is your filtration?

This is a long held myth started by those who provide filters for Aquaria. Bacteria live on every surface, including the water column. Thats why it's a common occurence for Fish to die if one does a 100% gravel vac. Bacteria also need to be able to feed on something. If you continuously replinish your water without the proper sized BBC to sustain the inhabitants of the tank, then you will essentialy starve the needed bacteria to death as they will have nothing to feed on.

* This is not a post against doing water changes. This is a post that advocates proper timing when doing water changes.

 

[Bigge_al]

I by no means am saying I will not be doing PWC I just will be doing them less frequently maybe once a month with the gravel vac. I also was doing a 100% vac I get that maybe that was not the best idea either so I back off that too to maybe a 25-50% per month that will remove the right amount of water.

 

[jlk]

Can you please explain why you believe its a 'common occurence for fish to die if one does 100% gravel vac'? I have never had fish die from 100% gravel vacs nor have I had fish die from removing 100% of the gravel & replacing it with a different substrate. Many members have successfully switched substrates without a single issue (with the exception being an occasional mini-cycle).

 

[KaylNeko]

I think the mini-cycle is the key word--if not monitored, it can get out of hand before the BB can get control of it and kill sensitive fish. Plus, I suspect if a tank doesn't have enough biological filtration capacity and the gravel is taking up the slack, that would send it into another cycle.

 

[aquaponicpaw]

Can you please explain why you believe its a 'common occurence for fish to die if one does 100% gravel vac'? I have never had fish die from 100% gravel vacs nor have I had fish die from removing 100% of the gravel & replacing it with a different substrate. Many members have successfully switched substrates without a single issue (with the exception being an occasional mini-cycle).

It's a common occurence because some might not have the proper amount of bacteria established in their mechanical filter. It's a huge variable. Just like some can completely change their filter media and not have deaths within the tank. whie others will lose all of their fish if they do a 100% change of filter media. That is why it is advised to do partials with Aquariums. And the wrong percentage of a partial will cause deaths.
More often in newly setup tanks than well established ones.

 

[absolutangel04]

This is a long held myth started by those who provide filters for Aquaria. Bacteria live on every surface, including the water column. Thats why it's a common occurence for Fish to die if one does a 100% gravel vac. Bacteria also need to be able to feed on something. If you continuously replinish your water without the proper sized BBC to sustain the inhabitants of the tank, then you will essentialy starve the needed bacteria to death as they will have nothing to feed on.

* This is not a post against doing water changes. This is a post that advocates proper timing when doing water changes.

I disagree. Some bacteria do float around in the water, but not enough of them to matter in the aquarium nitrogen cycle.
Most nitrifying bacteria involved in this process are basically non-motile. They secret sticky substances to stick onto surfaces like the substrate and colonize there. They are able to convert more ammo over because they don't have to waste energy moving around. Nitrobacter species are like this. Some Nitrosomonas are motile, but they are not as common.

 

[jlk]

It's a common occurence because some might not have the proper amount of bacteria established in their mechanical filter. It's a huge variable. Just like some can completely change their filter media and not have deaths within the tank. whie others will lose all of their fish if they do a 100% change of filter media. That is why it is advised to do partials with Aquariums. And the wrong percentage of a partial will cause deaths.
More often in newly setup tanks than well established ones.

The wrong percentage of a partial 'what' will cause deaths? Filter changes? Water changes? Gravel vacs? Please clarify your statements.

 

[jetajockey]

I disagree. Some bacteria do float around in the water, but not enough of them to matter in the aquarium nitrogen cycle.
Most nitrifying bacteria involved in this process are basically non-motile. They secret sticky substances to stick onto surfaces like the substrate and colonize there. They are able to convert more ammo over because they don't have to waste energy moving around. Nitrobacter species are like this. Some Nitrosomonas are motile, but they are not as common.

I agree with this. Nitrifying bacteria do have a degree of motility, but it has been long proven that they adhere to biofilm in the tank and reproduce there. If anything, the mythology being presented in this thread is the idea that there is a substantial amount of nitrifiers present in the water column. It has been proven false time and again.

There isn't a conspiracy by filter manufacturers, there is proof behind filtration harboring the majority of nitrifiers, the work that was done by Hovanec with the biowheel shows that clearly the concentration lies in the area where the optimal temperature, food and oxygen source are present.

I do however agree that people tend not to give the substrate enough credit. A LOT of things go on in substrate that aren't even considered, and it is often assumed or speculated that there is little bacterial activity in that area which is another misnomer.

 

[absolutangel04]

I agree with this. Nitrifying bacteria do have a degree of motility, but it has been long proven that they adhere to biofilm in the tank and reproduce there. If anything, the mythology being presented in this thread is the idea that there is a substantial amount of nitrifiers present in the water column. It has been proven false time and again.

There isn't a conspiracy by filter manufacturers, there is proof behind filtration harboring the majority of nitrifiers, the work that was done by Hovanec with the biowheel shows that clearly the concentration lies in the area where the optimal temperature, food and oxygen source are present.

I do however agree that people tend not to give the substrate enough credit. A LOT of things go on in substrate that aren't even considered, and it is often assumed or speculated that there is little bacterial activity in that area which is another misnomer.

Yes, good point about biofilm. I meat to add in my last post, but apparently forgot, that one reason some people have issues after large pwc is that they will let the biofilm dry out and the bacteria die. Of course, its hard to make generalizations about things like death after pwc because the specifics can be so different.

To the OP, if your tank has only been up for 2 months, there are all sorts of reason that a few fish could have died. I don't think cutting the pwc back to once a month is a good idea. It can set you up for problems later if you develop old tank syndrome.

 

[aquaponicpaw]

I disagree. Some bacteria do float around in the water, but not enough of them to matter in the aquarium nitrogen cycle.
true! But nitrifying bacteria are not the only bacteria present in the Aquarium.
Most nitrifying bacteria involved in this process are basically non-motile. They secret sticky substances to stick onto surfaces like the substrate and colonize there. They are able to convert more ammo over because they don't have to waste energy moving around. Nitrobacter species are like this. Some Nitrosomonas are motile, but they are not as common.

Spot on about nitrifiers.

The wrong percentage of a partial 'what' will cause deaths? Filter changes? Water changes? Gravel vacs? Please clarify your statements.

Any of the above.

I agree with this. Nitrifying bacteria do have a degree of motility, but it has been long proven that they adhere to biofilm in the tank and reproduce there. If anything, the mythology being presented in this thread is the idea that there is a substantial amount of nitrifiers present in the water column. It has been proven false time and again.

There isn't a conspiracy by filter manufacturers, there is proof behind filtration harboring the majority of nitrifiers, the work that was done by Hovanec with the biowheel shows that clearly the concentration lies in the area where the optimal temperature, food and oxygen source are present.

I do however agree that people tend not to give the substrate enough credit. A LOT of things go on in substrate that aren't even considered, and it is often assumed or speculated that there is little bacterial activity in that area which is another misnomer.

You are correct with everything . except conspiracy is not my word. I said myth which may not be the correct wording also. What I mean is because manufacturers and studies show that mechanical filtration harbors the most nitrifiers. Most Aquarists have taken it upon them selves to discount the bacteria that resides within the tank itself. And these are just as vital a colony as the one located within the filter.

 

[foster53]

There are definitely BB in the gravel bed as stated. When I started keeping fish all we had were undergravel filters, so the bacteria didn't have HOB's or canisters to colonize!

 

[Johnno1234]

I just learned the hard way that aquaponicpaw is completely correct. I hadn't had a fish die for approaching a year (48 litre tank, with 4 x corydoras, 6 x guppies, 1 x Kuli loach and 5 x neon tetras, which was a little overstocked and everyone was doing just fine!).

Last week I did a complete substrate change and swapped a couple of ornaments. By the next morning ALL of my tetras were dead. The corydoras, loach and guppies all made it, but they weren't happy at all (coming up for air all the time, the loach was going crazy). I realised what the problem was (total lack of bacteria) and took an old ornament, old plant and some of the old substrate out of the bag I'd put in the outside bin (which overnight would have reached almost freezing temperatures!) back into the tank. After a few hours, everything was looking better and now 5 days on I am beginning to see bacteria building up on the glass again (never been so happy to see dirty brown marks on the tank!).

I guess the moral of the story is A) don't take too much "dirty" stuff out of your tank at the same time, and B) bacteria lives for a LONG time outside of the water, so if you make a mistake just stick something covered in it back in the tank and hope for the best!

Strange how ALL the tetras died, but none of the guppies, corydoras or the loach. I guess they aren't as hardy to new water conditions!

 

[jetajockey]

I just learned the hard way that aquaponicpaw is completely correct. I hadn't had a fish die for approaching a year (48 litre tank, with 4 x corydoras, 6 x guppies, 1 x Kuli loach and 5 x neon tetras, which was a little overstocked and everyone was doing just fine!).

Last week I did a complete substrate change and swapped a couple of ornaments. By the next morning ALL of my tetras were dead. The corydoras, loach and guppies all made it, but they weren't happy at all (coming up for air all the time, the loach was going crazy). I realised what the problem was (total lack of bacteria) and took an old ornament, old plant and some of the old substrate out of the bag I'd put in the outside bin (which overnight would have reached almost freezing temperatures!) back into the tank. After a few hours, everything was looking better and now 5 days on I am beginning to see bacteria building up on the glass again (never been so happy to see dirty brown marks on the tank!).

I guess the moral of the story is A) don't take too much "dirty" stuff out of your tank at the same time, and B) bacteria lives for a LONG time outside of the water, so if you make a mistake just stick something covered in it back in the tank and hope for the best!

Strange how ALL the tetras died, but none of the guppies, corydoras or the loach. I guess they aren't as hardy to new water conditions!

Hi I think you experienced what some people call 'old tank syndrome'. I experienced this myself a couple of times years ago when I thought water changes only had to be done once every 6 or 8 months.

What happens is a tank that has been neglected for a long amount of time (as in no water changes for a very long period of time) ends up having a very high level of TDS and the pH tends to drop very low. The major shift in TDS with a big water change affects fish, especially sensitive tetras. The other thing about the pH is that as it drops, nitrification slows down, and this leads to a buildup in ammonia levels. This isn't a problem in a tank with low pH though, because another effect of a low pH is that the free ammonia (NH3) becomes ammonium (NH4), which is far less toxic.

However, when a big water change is done after all this time, the pH jumps back up to normal and the ammonium reverts back to ammonia suddenly becomes toxic again.

Bacteria is invisible, you won't be able to see it, but can sort of 'feel' it as the slimy stuff on the tank surfaces. The brown stuff on the tank walls is diatom algae.