I recently purchased Fish Tycoon and am loving it (currently have it playing as I write this, hehe) but I looked at the help and faq pages and haven't found some answers I need.
1) The health on my fishies are low, how do raise their health?
2) When fish are in the selling tank I found out they can still give birth and can feed them but does their health go down? Will I be able to raise the babies and sell them later?

Thats it for now, thanks for the help!

Health is not related to which tank the fish are kept in. Health will go down if they get a disease, are not fed, or if Fish Environment is not researched sufficiently for a particular breed. Once it goes down, the only way to raise it is to eliminate these three obstacles. Most fish will get better, unless their health is so low they are beyond help!!

Declining health in the offspring of fish that you breed at the beginning of the game is a common problem for people who are playing Fish Tycoon for the first time. Although the description for Fish Environment says that it "allows rarer fish to survive and thrive in your tanks," it's not very clear that only the common fish types will thrive in a level one tank environment. You can see tips, by clicking on the posters in the Fish Store, that deal with that issue.

Hybrid species in a Level 1 Fish Environment will typically continue to lose health until they die. The only thing that will restore their health (temporarily) is Fish Vitamins, but their cost is usually much more than the fish is worth.

The best approach is to discover fish that do well in the starting tank environment and sell for more money than most of your starting fish. There are several fish that do reasonably well in your starting tank environment and are good money-makers (selling for $25-50 or more). As soon as you have enough money, start researching better Fish Environment. You'll soon be able to successfully breed the more fragile hybrids.

The selling tank can be used to breed and raise fish. Just be careful that you don't accidentally sell a fish that you wanted to keep. The only real difference between the selling tank and the other two tanks is that any adult fish in the selling tank will be "for sale" when you enter the Fish Store by clicking on the "Sell Fish" button.

The thing is my normal fish which I began with are becomming unhealthy, that's the problem ;.; alot of my babies are dying so I'm trying to breed those purple ones to sell for environment upgrade. I got the food upgrade already which I read was a bad move (bad me ;.; )

If the fish that you started with are becoming unhealthy, then they are either sick or starving. The original fish can live indefinitely as long as they are properly cared for. Check the two "meters" in the lower right corner just below the tank while one of your fish is in the isolation tank or while you are holding it. The top meter displays the fish's current health, and the bottom meter displays how well fed the fish is. When the bottom meter turns yellow, it's time to feed the fishies. If the Fed Meter is red or (yikes) totally white, your fish are starving.

To determine if a fish is sick, just grab it and look at that black area above "Your Cash." If your fish is sick, you will see the word "Sick" in that display area. You should either cure the fish or trash it, since disease can spread among your fish population. A description of each type of disease can be found by clicking on the two different treatments in the Supplies Shop.

My fishes are invincible with the orange snooper.

They're not sick and I feed them regularly, never drops below 25% actually ^^ I just don't understand why it goes down o.O

What's an orange snooper? Is that a fish?

Yes, it's a fish, and it benefits the health of your fishies, as Archmage noted. But he is playing a PDA version of Fish Tycoon, and he has done some very atypical things with the game. Most people won't experience many of the things that he's posting about Fish Tycoon and Plant Tycoon.

There is a possibility that you're overfeeding your fish. If you don't wait until their Fed Meter drops to less than 50%, your fish will lost some of their health with each feeding. When I was testing Fish Tycoon, I actually fed some fish to death.

If you don't think that's the problem, either, perhaps you could give me the names of the species of fish that you're having trouble with - more information is sometimes helpful.

Oooh, the orange snooper sounded sorta pretty, orange and yellow are such bright, happy colors ^^

I think my problem is overfeeding ^^; I get nervous and feed them alot, eek, gonna have to watch that now.