Breeding Fishes

My pump from ebay came in yesterday. I thought it was going to come in today so I didn't buy the filter medium for the filter. I finished my new PVC overflow the other day with the 3/4 inch PVC instead and I am so glad that I did. I first tested my new pump with the 1/2 inch PVC overflow I initially made and the pump was way too strong for the overflow. Water was coming in way faster than the water was going out so this would flood my tank within a few minutes. I then put my 3/4 inch PVC overflow in and this overflow was stronger than the pump.
When making a PVC overflow, it is necessary for the overflow to be stronger than the pump. This is because the overflow must be able to handle the amount of water being put in. It is okay that the pump is much weaker than the overflow because then the water will not over fill the tank and only the amount of water being put into the tank will go down the overflow without over flooding the tank. Its a little complicating and hard to imagine but once you do some tests and trials, you will understand this.
So my PVC overflow works well with my new pump. I am so glad I didnt have to make a larger overflow because the 3/4 inch is already big and visible enough. Today I will finish off my filter by buying an output tube, filter medium, and plastic pot scrubbers (as a cheap alternative for bioballs). Once I buy all the materials and put it together I will do a DIY post of the overflow and the filter.
So I decided to breed some fishes for my turtles to eat. I know that minnows are the cheapest but I've never had experience breeding minnows so Im a little worried about doing this. I feel like it is much harder because you must raise eggs and such. I've bred guppies before and I find those the easiest since they give birth instead of laying eggs. Guppies, on the other hand, are much more expensive. Most of the time they die really quickly and I find that it is such a waste of money. I can not decide which is the best choice. I guess which ever breeds the fastest will be the best. I would like to have enough fishes where I can feed my turtles a fish each every other day.
I took some minnows out of the tank and put them in a separate container. I put a PVC tube inside, hoping they will lay their eggs inside. I will try to breed the minnows and if I feel that nothing is happening, I will resort to guppies.

The turtles are starting to really warm up to me. They now shallow water bask in front of me without running away when I look at them. Of course they will always be a little skittish and duck when I come near the tank but once I sit down and they see that I am no threat, they will then bask in front of me. Today I fed them some floating fish pellets. I wanted them to get used to eating floating pellets since I want to add turtle pellets to their diet. Since I had ciclid pellets and koi pellets laying around my house, I threw some in and the turtles immediately came up to eat them. I think I will go to the pet store tomorrow and pick up some turtle pellets. I fed the turtles pellets one by one today. I wanted the turtles to see me throwing the pellets in as they ate them. I feel like they will warm up to me faster once they realize that I am the one giving them food. Instead of just throwing it in without them looking and them thinking the food is coming from heaven. haha. I try my best not to disturb them. Even though I want to pick them up and hold them, I tell myself to leave them alone so they dont become scared of me and see me as a threat. Hopefully they will be 100% comfortable with me very soon. I just hate when they hide from me and I have to wait 20minutes for them to finally come out and take a breather, just to run back under the wood.