Filter Help?

[Ruthc1985]

I had two sucking loaches, never again! far from peaceful fish, they bullied my other fish, nipped tails and made them bleed, and one became dominant. Ended up rehoming both! Started off teeny, ended up small beasts............

Changing to a new pad every 4-6 weeks is a very bad idea, bacteria are colonising the pad and then you remove them from the tank, possibly sending the tank system into a "mini cycle." Pads/sponges should be rinsed in removed tank water (like you are doing) and kept until they are falling apart, typically years later, then only changing one pad/sponge at a time over a week or so.

Do you have a liquid test kit for ammonia and nitrite?

If not, the best thing you can do is 50-95% water changes daily, so at least you can be reasonably sure the water is not getting too toxic.

Scour the second hand market for a tank, the bigger the better, to make it worth while at least a 4-foot 150l or more for now (there are deals out there, 5-footers can be had for <£100 if you are in the right place at the right time). But in the long run, as already said, goldfish need massive tanks (6x2x2 plus, but ideally a pond) as do Chinese Algae Eaters (who often get aggressive as they age, rasping on flanks on tankmates).

I change my biological filter only when it looks rubbish, maybe every year to 18 months? Only ever changed my current one once in 2 years when it became mishapen and a bit minging.

As for second hand, try preloved or gumtree

 

[OldMan47]

Welcome to our forum Helen23254.
It sounds like you are doing the right maintenance on your tank already. The filter, no matter how big, will not remove all solid wastes. That is up to you and your siphon to take care of. The filter is there to remove organic poisons like ammonia, not solid wastes. With a properly cycled small filter, the ammonia is being taken care of and you just need to change enough water every week to remove the solid wastes and to reduce the nitrate concentration to a reasonable level. With your fish population and tank size, I would suggest that at least half the water get changed every week.
There are a huge number of small fish that suck on algae on the glass so unless you can post a picture we will probably never identify your fish correctly.