Why No Prob With Bare Concrete Tank In Backyard Options

[max]

goldfish keeping has become pretty complicated these days , remember cousin of mine used to have a concrete tank 8x3x2.5 cemeted to the floor in his backyard way back in Lorong Ah Soo kumpung days.

There isn't any need for filtration, it is just like throwing the fish in & it will survive. Left in the open you have green water, so green that you can't see the occupants at all not until it surface for food . I remember they is no Hikari or Tetra food, just humble white fish bread, only 0.30 cent. a package & the goldfish wahsay man puipui sweeswee one.

Water change is about once in every 2 months, no drainage system just the tradition way of removing all the fishes, scoop out the water & re-introduce the fish & bingo! .

Can anyone explain why such a method of fish keeping is possible those days & why can't it be the same today?

[HappyBuddha]

goldfish kept in green water is known to have faster growth & rounder body maybe due to the presence of algae pores floating around which they can feed on.  I don't have green water in my tank but I've thick algae growth on the glass which I see the goldfish constantly nibbles on, will the result be the same as green water? 

Those thick alage growing on walls and floor are excellent in another way I know of. First of all, they thrive in nutrient rich filtered water. Now we know the end result of bio-filtration is nitrate. Although relatively harmless compared to ammonia and nitrite, high concentration is still not good. However, plants and alage has the ability to used up nitrate. Your filtered tank is thus superior compared to one without any plants/algae.

I'm not entirely sure if eating the algae is good. It's harmless for sure but the quantity the fish is able to nip on is very small. The benefits of consuming the algae is thus quite limited.

My point is the algae being presence in the tank helps give you good water parameters hence providing an excellent environment for your goldfish.

I've been dying to have some in my display tank! You're so luck to have them.