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Fluval U2

I did have a Tetra easy crystal ECF box 600
But it was bulky and only had a filter bag
My reading are now
Ammonia . 50ppm
Nitrites . 35ppm
Nitrate 5.0ppm
Set up your U2 filter as per this video. Get rid of the cartridges and jam in some sponge instead. You then dont need to change anything until its literally falling apart, which should be 10 years at least. All you need to do then is periodically rinse the sponge in dechlorinated water to stop them getting clogged up. Maybe do this every month or 2, but if you see water flow significantly reduced, rinse the sponges.

I personally think the filter is too small for 100 litres, especially as you are keeping goldfish. I agree with richard in the video, its a good filter for 60 litres. You normally want to half the rating for filters to get an idea of what they actually are good for, and you want to double the filtration for goldfish because they are very messy fish. If you are looking at fluvals U series internal filters, i would be looking at the U3 at the very least, but really the U4 is more suitable for a couple of adult goldfish in a 100 litre aquarium or an external canister like a fluval 307 would be better still.
Gosh who knew ! I'm regretting starting this now. The aquarium I mean.
I'm certainly not purchasing anything else as I've already spent too much on treatments, filters, stuff.
I have taken his advice and packed the filter sides with sponges rather that the cartridges. I've ordered more filter bio media for the middle to see if that helps, as there is only half the capacity with bio stuff in there. I have a smaller filter that I kept from another small tank so I could pack that with the bio stuff too and have 2 going.

Hopefully there will be a difference soon. Thank you.
The whole aquatics trade is designed to get you to part with your money. Manufacturers will overstate the effectiveness of their equipment, market supplements that dont do what they claim, or dont do anything useful, all to get you to buy their stuff over someone elses, or get you to buy stuff you dont need.

Do things right, and do it once is the order of the day. And as for treatments, the only product you really need is water conditioner, and plant fertiliser if you have live plants.

Here's some valuable advice to save you some money. Instead of tetra aquasafe for your water conditioner, get seachem prime or api aqua essential.

500ml of aquasafe is around £12. It will treat 1000 litres of tapwater, so £1.20 per 100 litres of water treated.

500ml of prime is around £21. It will treat 20000 litres of tapwater, so £0.10 per 100 litres of water treated.

473 ml of aqua essential is around £12. It will treat 18000 litres of tapwater, so £0.07 per 100 litres of water treated.

Both prime and aqua essential are far better products than aquasafe as well.

Those arent typos, thats £1.20 compared to 10p and 7p for a 100 litre water change.
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Yes of course you are right and I'm guilty of falling into the trap.
So my only choices are
Get rid of the fish and tank and the stress. Put down to experience.
Or persevere and see no real let up for 6 months...maybe.
I'm favouring the first option at the moment.

Know anyone who wants some fish and kit?
Days on.. after 5 x 50% water changes
Extra filter
Added bio stuff
Packed the filters with more sponge as much as will fit
Prime concentrated water conditioner
Less feeding

The Ammonia and Nitrate levels combined are reading 4.0 this morning
So another water change to do.

This is driving me nuts.

Nothing I am doing after followng all advice is making the slightest difference.
Ill say this one last time.

Expecting anything to change after a few days is completely unrealistic. Under ideal circumstances it can take a couple of months to cycle a tank. You arent doing this under ideal circumstances. You are keeping temperate water fish, so the water temperature is 7 or 8c below the ideal temperature to cycle the tank and you have too many fish for an uncycled tank so the water quality will deteriorate quickly meaning you have to do frequent, big water changes to keep the water at a safe level for those fish.

I go back to to the "do it right, do it once". If we were starting from scratch it could all be a much easier, quicker process. What you are seeing isnt uncommon with new fish keepers though, most have no understanding of the nitrogen cycle or how to cycle a tank, and have problems to start with. But the fish are in your care, and you have a responsibility for their health.

If you arent all that bothered, then just stop doing the frequent water changes. Historically, many people cycled tanks by throwing a load of fish in an aquarium and doing infrequent water changes. When the fish died, they got replaced. When they stopped dying the tank will have cycled. But one of the principles of this forum is to be ethical and be responsible for the fish in your care, so i can't support you if you dont have a basic duty of care for the fish you bought.
Your frustration is the same as mine.
I get it that the cycle will take weeks/months.
I have increased the water temperature to 22 /23c

And I am prepared to continue with water changes.
Each time I do one I am expecting the slightest improvement to be progressive however it isn't.

So if the "cycling" takes weeks etc does all of a sudden bang it works. Because the water changes approach is not showing any permanent changes. So something must just happen suddenly and what is it that creates that change. And why can't I just do it quickly.
It really depends on how fast those microbes you need grow. Under ideal circumstances, i believe they can double in number in 24 hours. So under those circumstances, yes you typically see a very rapid difference at the end of the process. For example

1 x 2 = 2
2 × 2 =4
4 × 2 = 8
8 × 2 = 16
16 x 2 =32
32 x 2 = 64
64 x 2 = 128
128 x 2 = 256
256 x 2 = 512
512 x 2 = 1024
1024 x 2 = 2048
2048 x 2 = 4096

So with this doubling of numbers, all the work is done at the end and you hardly notice the doubling at the beginning because the numbers are so small. But you need those initial small steps to accumulate over time so that you can get to the big numbers at the end.

But you arent at that ideal circumstances, you might only be getting a 50% improvement every day, 50% of those small numbers at the beginning is less noticable and it takes much longer for those small numbers to build up. Your tests are nowhere near accurate enough to differentiate one day to the next, you would probably need to compare one month to the next to see any appreciable difference.

Try and do the same exercise of increasing by 50% per day and see how much longer it takes to that 4000 number in my example.

You are seeing nitrite in your test, so your cycle has established to some degree, so you arent at the very beginning of those small numbers, but it takes time for those microbes to grow and establish in your filtration.

There are a few shortcuts you can take to get those small numbers up quicker, so you skip a lot of those early steps. For example the bacterial supplement you mention in one of your early post. Problem is, those products mostly dont work. The live bacteria are either already dead by the time you buy the product, or more likely they were never in the bottle to start with and you just bought a placebo. Some people report success, most people dont. If you want to spend money on these products then go for it, but you are probably wasting your money and could literally tip £100s in your tank to no effect. Another option is use some filter media from an already established aquarium filter if you know someone with an aquariun who would let you have a little. But these 2 options wont instantly cycle a tank, it just cuts down on some of those early steps as the microbes still need to grow and colonise throughout your filtration media.
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I understand that explanation thank you.

I will continue with this method and hopefully the fish will survive. They all feed and swim around happily so that's all I can do.

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