golden algae eater suddenly chasing other fish.

[merlin777]

Something odd started happening today. My golden algae eater has suddenly started chasing other fish.

Until today it has been placid and rarely went above the bottom of the tank.

I have:
a fresh cold water biorb
1 golden algae eater (about 3inches)
4 other fish (2 dannios and 2 minnows) about 2.5 inches

I changed half the water 2 days ago (it hadn't been changed for quite a while)
the weather has warmed up today (I'm in the UK)
I added 3 zebra nerites today but they are still dormant

Any thoughts as to what has caused this sudden change in behaviour?

[absolutangel04]

This is what most all golden algae eaters do. They are actually a semi-aggressive fish and once they reach a certain size, they acn be downright nasty. The reason for the behavior change was the fish maturing, not anything that you did.
Is your tank the 8g biorb?

[Smcoyle87]

Sounds like it's a Chinese Algae Eater, and it's normal for them.
Just to be clear, is it a pleco??

CAE get aggressive and temperamental as they mature. They will try and eat the slime coat off other fish in the tank! They grow to be a good 6 inches as well.
For your sake (in MY opinion) I hope it's a pleco that's just acting weird for some reason.

[NYgiantsRP]

If it is a Chinese algae eater it can become aggressive when it reaches full maturity. If it is only an 8 gallon tank you have to donate that to your local fish store ASAP.

[merlin777]

its the baby biorb so I'm at capacity with these 5 fish, I think.

I'll try to add a couple of photos but they'll be a bit iffy!

Why suddenly change today? Would the warmer weather and cleaner tank have woken him up a bit?

[NYgiantsRP]

Could have. But you have way too many fish in that tiny tank.

[absolutangel04]

Actually, I am sorry to say that you are over capacity with those 5 fish. That will not help the situation, just so you know. I suggest re-homing him. Also, I suggest looking into your other stock as well to see if they are really the best fit for your tank. Most commonly available danios do better in larger spaces.
Pretty much all the fish you buy in pet stores are babies. They grow, and mature. Territorial behaviors tend to come out with maturity. Why today? Because today is when the fish matured. I honestly don't think there is more to it than that. It was going to happen eventually.
Yes, Chinese algae eater is the same things as the golden algae eater. Just 2 names for a fish that comes in more than 1 color.

[merlin777]

oh, dear - looks like i've got some work to do. Thanks for your help, everyone.

[merlin777]

Originally Posted by merlin777

oh, dear - looks like i've got some work to do. Thanks for your help, everyone.

I've just been sitting here, fish watching, and it's not just the GAE that's chasing the others. They all seem to be doing their fair share of chasing each other.

Any thoughts?

[Smcoyle87]

The tank is too small for those fish and the danios and 'minnows' are schooling fish. Schooling fish get nippy when there aren't enough of them.