No problem there, I have a local fish store that will take them and trade them in for smaller ones when I need too. I enjoy the koi so I buy them small 3-4 inches. Only 2 in there, Who knows I'll probably build a 700-1000 gallon pond when they get bigger. Its not that hard to build a pond. I enjoyed it actually...Here's a couple of pics of the 160 gallon pond 7'X5'. The pics dont really do it justice..I still have to get the slate this week and put that in..I'm also making a Bakki shower for it was well. My fish will have a nice condo for them ...lol
Great Idea - as 6in Koi are worth about 30 times 3 in ones you might even run at a profit !!
Only comment would be that you need to plant something right next to the pond so that at least one third of the water area is in the shade, surprisingly fish do get sunburn if they can't get out of it.. Also for a new pond the water must not become alkaline as it can from stones, slabs and other building materials. Check every week and just use vinegar or diet soda to bring it back to nuetral
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