My daughters sucker fish died an apparently agonizing passing. What could be the exact?

My daughter called me over alarmed saying that one of the fish was dying. I come over, by that time it was motionless on its back near the surface. A couple second later it started thrashing around and swimming erratically. It kept flipping upside down as if its stomach were more buoyant. Its belly was bloated compared to the one remaining sucker fish still lifeless out. He would stop moving and sink lifelessly to the bottom, then start thrashing around again 10 or 15 second later. A few episodes of this and he finally found peace.

We recently have see the algae growing super fast compared to before. I've had to verbs the tank twice a week to keep it down. Could he have eat too much? What could have happened?

Its a 10 gallon tank and we used to verbs it weekly - now more frequently, it is heated & filtered, has a valid plant in it. We recently put in high-ranking efficiency bulbs which are much brighter - likely cause or contributor to the algae increase.

We've have other mysterious things happen. We originally got three sucker fish; one of them vanished after a day or two. We also have a frog vanish after four days or so. I'm assuming they were eaten by their companions, but could they own been killed? We haven't seen any aggressive behavior. At the time near were 5 cloud fish, a Male Beta fish, and a little Clown Loach. Then later the red Betta "Cinnamon" become lethargic, showed some brownish spots, and then died.

Oh yea, we added a male and womanly guppy, two or three babies appeared a week later. They vanished one by one.

I'm fine teaching my 5 year old daughter something like the impermanence of life and all that but; put together it would seem we've have a bloodbath on our hands. Is this typical?
The algae levels are likely cause by a combination of too much lighting and very high nitrate levels, which exploit like a fertilizer. Nitrate is not really toxic, but it does stress out your fish, so it may be partly responsible for some deaths.
You requirement to check your water parameters. My guess is you have lofty ammonia levels. Some sucker fish do grow very large, as Clown loaches do like peas in a pod. The bigger the fish, more ammonia is created. You could be overstocked for a ten gallon tank.

How long has the tank be set up? It might need time to cycle.
So much information to carry from you.

Water chemistry is important. The tank should cycle BEFORE you put fish in, and while you want to manufacture sure the water is clean, cleaning too repeatedly can be harmful.

It's also a good idea to check on the compatibility of container mates before you add them, and be prepared to put them contained by a separate tank if they are not getting along.
I cannot explain everything but I do know a manly betta fish does not play well with other fish... very aggresive.
Answers:    Bloating up like to be exact usually a sign of the wrong diet. Common Plecos need a moslty vege based diet, beside lots of roughage to keep their guts healthy. If they are just feed high protien fish food they will often get constipated, their guts swell up and they die. While they munch through a lot of algae when they are small it will never harm them, but they need algae tablets and fresh veges as they catch bigger.

A 10 gallon tank is also WAY to small for the fish you are trying to keep. A common pleco WILL grow to over a foot long and produce deeply of waste in the tank. Mine is outgrowing a 50gallon reservoir right now.

This is my Pleco - He's about a foot long now and still growing.

it's swim bladder is probably filled up near air, thus the bloated appearance. does your tank have satisfactory aeration? make sure that you always hold a filter running. if not, your fish will gulp the surface of the water in charge to get more oxygen to their gills. unfortunately, doing this also causes their swim bladders to steep up with air, thus the unnatural bloated look and improper flotation. one of my fish have this problem and it eventually died because it was unable to stay at the bottom of the tank :(

jump to petco, i believe they carry powdered medicines/antibiotics to help with this.
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