Switching canister filter safe? or will I loose all my good bacteria?

Agreed! Although rinsing out (in old water) reusable media from the Mag 350 that has been running for month with strong flow (a testament to its superiority) and placing that established media in a new Mag 350 will work, It is far better to add the new Mag 350 to the tank side by side with the old for a period of time (1 month) and like a relay race handing off a baton the bacteria will be established in the new filter.

Why I run two filters so that I can completely clean one while the other remains and I have never had a spike even if I decide to replace all the media when using 2 filters.

However in your case having waited so long, you probubly should not wait any longer and old water rinse the old media, however clean the canister body, impeller & chamber, valves and hoses with very hot tap water the tube & cable brush provided. Then just put that proven Magnum 350 back in service.

As for the gnats I have never heard of such a thing except around fruit bowl or plant soil in flower pots. The gnats have nothing to do with the canister filter, maybe an HOB power filter but not a canister like the Magnum.

I can see the gnat larvae in my water. There are literally hundreds, if not thousands. They look like tiny bubbles. Why do you say they can't live in the magnum filter?

btw, how loud is your filter? Some people say there's literally no sound... but mine is clearly audiable.
 
Would you guys happen to know how if sand holds bateria well or not?
I'm sure there is some bacteria on the top of the sand but considering how compact sand becomes when used as substrate, there's no flow between each granule and therefore no way for the bacteria to survive, unlike individual grains of gravel. Did that make sense?
 
I can see the gnat larvae in my water. There are literally hundreds, if not thousands. They look like tiny bubbles. Why do you say they can't live in the magnum filter?

btw, how loud is your filter? Some people say there's literally no sound... but mine is clearly audiable.
try pulling apart the mag and getting down into that little well where the impeller sits. it's very possible you've gotten some grains of sand down in there.
 
All you have to do is start the fish fasting for 2 days to minimize new ammonia. Then remove the filter and place the micron and sleeve in bleach water as per magnum instruction manual.

Then go out and buy or make yourself a new blue bonded sleeve and use the your optional basket instead of the cartridge filled with zeo-carb (carbon/zeolite) to help minimize ammonia spiking, and you'll be fine as far as ammonia spiking goes.

However the larvae problem will probubly not go away until you get a UV sterilizer and use it without a sponge or you completely strip down the tank and sterilize it with bleach. You can also try getting yourself a couple of small Goldie feeders that love that stuff and let them eat it all up, may not work though.

I would but the GKM UV sterilizer, remove the sponge and zap those floating babies with the ray gun. But tank cleach strilzation is th eonly way to be sure.
 
I posted once before in the original gnat thread but thought I'd throw it in here as well. When I encountered this problem it was in a freebie tank that a friend of mine was getting rid of. This had a small tetra HOB with the med. size filter cart. It had literally hundreds of larve in a cartridge that was onyabout 3"x5" and .5" thick, not to mention thousands in the gravel of a 10 gallon tank.
I'm afraid Gunner is right. If you put the new one into service without fixing the problem you're gonna transplant larve to a new filter and possibly suffer a mini cycle in the process. I would think it would only take one or two to repopulate the whole tank and new filter.
 
I'm sure there is some bacteria on the top of the sand but considering how compact sand becomes when used as substrate, there's no flow between each granule and therefore no way for the bacteria to survive, unlike individual grains of gravel. Did that make sense?

Yeah, that makes sense. thanks

try pulling apart the mag and getting down into that little well where the impeller sits. it's very possible you've gotten some grains of sand down in there.

I'll be sure to clean it out well... but can you hear your filter though? Like i said for some reason some people say its really loud, while some peopel say they can't even hear it. For me.. its not loud but I can definitely hear it working.

All you have to do is start the fish fasting for 2 days to minimize new ammonia. Then remove the filter and place the micron and sleeve in bleach water as per magnum instruction manual.

Then go out and buy or make yourself a new blue bonded sleeve and use the your optional basket instead of the cartridge filled with zeo-carb (carbon/zeolite) to help minimize ammonia spiking, and you'll be fine as far as ammonia spiking goes.

However the larvae problem will probubly not go away until you get a UV sterilizer and use it without a sponge or you completely strip down the tank and sterilize it with bleach. You can also try getting yourself a couple of small Goldie feeders that love that stuff and let them eat it all up, may not work though.

I would but the GKM UV sterilizer, remove the sponge and zap those floating babies with the ray gun. But tank cleach strilzation is th eonly way to be sure.

So don't use the new micron filter I have? What exactly does the UV sterilizer do?

I posted once before in the original gnat thread but thought I'd throw it in here as well. When I encountered this problem it was in a freebie tank that a friend of mine was getting rid of. This had a small tetra HOB with the med. size filter cart. It had literally hundreds of larve in a cartridge that was onyabout 3"x5" and .5" thick, not to mention thousands in the gravel of a 10 gallon tank.
I'm afraid Gunner is right. If you put the new one into service without fixing the problem you're gonna transplant larve to a new filter and possibly suffer a mini cycle in the process. I would think it would only take one or two to repopulate the whole tank and new filter.

Were the larvae easy to see? In the tank they literraly look like bubbles. I can't image how you would be able to see them on the filter...
 
What I saw in the filter and in the water were very similar in length to the lime green gnats. Perhaps there were two different pests going on at the same time. The only green gnat that I can find in reference to aquariums are the aphids. I was unable to find any good pictures of them in the aquarium setting though. It would also seem if those were the culprits your "bubble" size larve would probably be more acurate.
 
There is one other possibility, just do your normal filter cart cleaning in bleach as per sop and squeeze the sponge or any other re-usable media in old water to keep bacteria alive.

Then nuke the entire tank with a heavy dose of parasite medication, I mean a full dose and raise the temp to 90. make sure you have no carbon or zeolites in the tank or filter. If you use a good quality parasite killer, that should work.
 
What I saw in the filter and in the water were very similar in length to the lime green gnats. Perhaps there were two different pests going on at the same time. The only green gnat that I can find in reference to aquariums are the aphids. I was unable to find any good pictures of them in the aquarium setting though. It would also seem if those were the culprits your "bubble" size larve would probably be more acurate.

Yeah, these things are TINY. I can hardly see what the look like. I just know that they are little lime green insects with wings. And the larvae is tiny and white the size of a super small bubble. As they get bigger they get longer darker in color...

There is one other possibility, just do your normal filter cart cleaning in bleach as per sop and squeeze the sponge or any other re-usable media in old water to keep bacteria alive.

Then nuke the entire tank with a heavy dose of parasite medication, I mean a full dose and raise the temp to 90. make sure you have no carbon or zeolites in the tank or filter. If you use a good quality parasite killer, that should work.

If I sqeeze the old filter, I'll risk the chance of sqeezing all the larvae in my tank.

As for nuking the tank.. I don't think that'll be safe for my arowana.

If it comes down to nuking, I think I'l just have to deal with the problem until I upgrade to a larger tank.
 
Well, if you put a new filter on the tank while the larvae are still in the water column then they'll colonize the new filter regardless, along with the BB. If you want to get rid of their refuge, you'll probably have to put a few big sponge filters in the tank and then remove the canisters.
What you essentially have is the equivalent of a marine refugarium, except it's stocked with guys you don't want.
Even if the guppies eat all the worms in the tank, there will still be a breeding colony in the canister to replenish them.
I had a similar snail outbreak, where the loaches in my tank would eat all the snails and any that ventured down from the HOB, but they couldn't get to the ones in the filter.
 
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