Guppy Color Changes and Bullying Question

[PineSong]

I've had Endlers in the past, but my current guppies are the only dark-colored guppies I've kept.

They were sold as "Green Moscow" but are dark blue. I've noticed that they change from darker and more shimmery to lighter and less shimmery as they go about their activities. In the first few weeks in the tank, one of them would look very washed out and almost gray/yellow at times, and then bam, he would be blue again an hour later. Today, they are both very dark, almost black, and very shimmery--and also super annoying to the other fish.

Question #1: is this color change normal?

 When they aren't flaring and circling each other they are chasing Endlers away or zipping after the smaller of the two platies. 

Because of losses in quarantine/medicating this tank, it is low in population--there are 2 male platies and 3 male endlers for them to harass. (The guppies ignore the otocinclus.)

I believe the other fish are stressed by this harassment but I can't add more fish anytime soon--I have some in QT and it will be 2 weeks before they can go in. I'm debating putting the guppies in a breeder box on time out for a day to give the other guys a break. 

Question #2: assuming this is hormonally-driven behavior, how old do these guppies need to get before they knock it off? I feel mean depriving them of ladies if this is how they are going to act, but maybe this is just the teenage stage before they settle down and get interested in middle-age guppy things?

 

 

Edited July 25, 2021 by PineSong
Added photo of my "green" guppy, lol.

[Guppysnail]

The behavior will continue in my experience.  Male guppies do three things. Dominance behavior for breeding rights.  Chase girls and mate. Eat.  My one ended up killing a female CPD first non stop chasing then one day he started ramming her in the side. I got her out right away but the couple slams he got in before I could net her out were enough. The only things are add more males so the aggression is spread way out or add females. This is just my experience 

[PineSong]

Thanks, Guppysnail. I guess it was too much to hope for that they would age out of it. I am sorry about your CPD.  I am going to add even more plants and hope that the other fish can hang on until the new crew finishes QT and can join the tank to disperse the harassment. 

One of the main reasons I started this tank was to give my  betta a community tank to live in. He's not a fast swimmer at all because of a birth defect, so I expected other fish to be able to easily avoid him. I'm rethinking that now because I 'm afraid these 2 guppies would pester him to death. 

[lefty o]

mood, food, and lighting can make the colors change form blah to full color, all in the same day. some fish and colorations are more prone to it being more noticeable than others.

[PineSong]

On 7/25/2021 at 11:26 PM, lefty o said:

mood, food, and lighting can make the colors change form blah to full color, all in the same day. some fish and colorations are more prone to it being more noticeable than others.

Food......You know, I gave them frozen bloodworms for the first time on Friday, and their bullying seems to have increased. Maybe the worms put them in the mood?

[Guppysnail]

If they are slightly hungry the aggression energy is partially redirected too eating and finding food. Nice fully bellies and it’s show who boss is and oolala girls time. 

[PineSong]

Just an update. I put the big bully in a breeder box when I went to work for two days and let him out at night so the other fish could get a break from his nonsense but he could still eat and sleep as normal. I fed them only once per day for a few days and no more blood worms at all.

Both guppies have calmed down considerably; they are pesky but not at the level where the other fish will be stressed to death; the endlers who were hiding out from them are back out.

I will save the blood worms for my bettas at least until there are more fish in this tank to spread the harrassment around.