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Tank STILL not cycled! Wrong filter size.

5 replies

bellabelly · 16/09/2015 00:31

Thanks for all the great advice I've had on here before. Need some more advice...

Bought 60 Litre tank at end of July. Home for one fairground goldfish (common) and 6 white cloud mountains. Couldn't do fishless cycle as had already got goldfish.

My local fish shop sold me the tank (aqua one 40 cube) and a filter (interpet pf mini). I now realise that the tank will not be big enough for a goldfish in the long term but it will have to do for now.

I have been testing the water with an API liquid test every day - the ammonia level has been consistently 0.25 ppm or thereabouts and I have always had a 0 reading for nitrite and nitrate.

I have been puzzling over why the tank isn't cycled yet and today I realised that the filter I've been sold is supposed to be for smaller tanks - up to 40 litres - whereas mine is a 59 litre tank. Do you think that this is why I'm not seeing any nitrite or nitrate when I test?

I have ordered the Interpet PF2 which can deal with a larger tank than I currently have. In my situation, would you run both filters together for a while? Or stick a bit of sponge from original filter into the new one? Or just start again from scratch with teh new filter?

Any advice very gratefully received.

OP posts:
Creak · 16/09/2015 00:45

You can do it both ways, but I'd personally probably stick as much old sponge as will go in the new filter. And keep feeding to an absolute minimum, and small partial water changes frequently, if you're still getting ammonia. It will do its thing eventually, but will take a lot longer as you've already got fish in there and it's essentially playing catch-up. Is goldfish quite a large chap?

bellabelly · 16/09/2015 12:04

Thanks, Creak. That is definitely my preference because I don't want two filters cluttering up the tank if I can avoid it. I'll put all of the old sponges in and then see if I can fit in the new ones two. Am guessing it's best not to cram it too full of sponges so I could keep the new ones as spares?

I am a bit annoyed that the fish shop sold me the tank and a filter that is too small. I didn't even think to check because at the time I knew next to nothing about filters, cycling etc. Still feel pretty ignorant really but I am trying to learn!

Yes, "Red" the goldfish is growing and growing. He was tiny when we got him but I think he's about doubled in size since the end of July. Feel like an idiot now but I honestly had no idea that they can grow so big and need so much space. Long term, I think we need to find a friend with a pond for him although this will not go down well with my DS. Or get a MASSIVE tank - this will not go down well with DH, I feel...

OP posts:
pygmyangel · 16/09/2015 21:36

I would second putting the old sponge in the new filter along with some of the new sponges too. Don't cram it too full though or you risk damaging the filter motor. I would also recommend buying a bottle of Tetra Safe Start. This is the only bacterial filter starter that actually works and should cycle the tank in a matter of days.

bellabelly · 16/09/2015 23:26

Thanks pygmyangel, that sounds wonderful if it actually works! Will have a look.

So the new filter has arrived and is in the tank and it's HUGE compared to the old one. Also very noisy. Am wondering if I've done the right thing, it had better be very good indeed.

OP posts:
TreeSparrow · 17/09/2015 22:17

You'd be better off buying a large, cheap plastic dustbin or rubble bin and transferring fish and filter to that. Larger water volume = safer fish. At least until you can get a bigger tank.

Pet shops are generally HUGELY irresponsible when it comes to fish.

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