Fish Keep Dying

[LIL860]

Im at my wits end over the last week i have lost 5 guppies from my biube and today i lost one of my angelfish from my 220 litre tank.

Tested the water in the biube nitrite 0 and ammonia 0
Tested the water in 220 litre tank nitrite 0 and ammonia 0

So what could be happening guppies show no sign of illness i look in the tank and they are dead.The angelfish was quite happily swimming around the tank yesterday morning now it is dead. I have not used any chemicals or sprays around the tank. Any suggestions welcome thanks.

 

[WILDER]

Need to know stocking in each tank please.
Do any fish go pale or darker in colour.
Any fish act listless or lethagic.
Any fish stop eating.
Any fish gone thin or bloated up.
What does it look like when the fish go to the toilet.

 

[LIL860]

Biube contains guppies not sure how many approx 8 as they are too quick to count one is dying,2 neon tetras, 3 black neon tetras and 3 zebra danios and 2 x 1.5 inch angel fish(who will go in the large tank when they are big enough to) tank has been set up about a year. Fish eat have healthy poo, i have noticed them laying in the biorb media gasping before they die.Seems to only be affecting the guppies last bought 5 about 4 weeks ago only 3 of these left now could they have passed anything on to the other guppies.

220 litre tank contains 3 other angels, 4 inch parrot fish, pair of sailfin mollies, 5 small platies, 3 plecs, and two clown loaches. All fish are feeding fine swimming normally and pooing normal. I have noticed the clown loaches trying to go for my other fishes eyes could they have killed it.

 

[WILDER]

How many gallons is the boirb as it sounds overstocked.
Is there plenty of aeration in the tank.
Gasping means bad water quality, lack of 02 in the water, parasites.

 

[LIL860]

Biube is 35 litres the guppies lay on the bottom gasping dosnt affect the other fish just them then they die.
220 litre has two large air stones running so plenty of oxygen in there for them.

 

[WILDER]

That biorb is way overstocked and I bet there lack of 02 in the water.
Immediate water change.
Not one fish should be in that boirb there badly designed for fish and they don't make good tanks.

You need to take the angels out they shouldn't even be in that size tank.