• Looking to buy a cephalopod? Check out Tomh's Cephs Forum, and this post in particular shares important info about our policies as it relates to responsible ceph-keeping.

Can i add starfish?


Jul 11, 2003
I just acclimated my 2 black mollies to my tank, and i was wondering if it would be cool if it added a starfish?

Also, I have some questions about my mollies.
My two mollies look different from each other. One has a really big fin on its back and a big finlike thing under its pectoral fins, the other one doesnt. why is that?

My mollies arnt swimming much they stay at the bottom of the tank inbetween some rocks, should i be worried? Also, when i was slowly adding in water from my tank to their water one jumped out :!: .

P.S. my substrate is starting to get these yellow paches on it is this normal?

thanks in advanced
Hi Rockthis,

It's too early to be adding other things to your tank. One step at a time!

It might be good if you'd tell us again what you ended up with in the way of a tank. Did you end up with a 50 gallon? Does it have a sump or not? How much live rock? What else do you have?

You will notice changes and things slowly beginning to grow on the live rock, small animals, etc. That's part of the fun!

All the best,
The molly with the big fin is the male, he has a special fin underneath called a gonopodium which he uses when mating with the female... they will need time to settle in before they act normally, just give them plenty peace and they will come round.

you will get algae blooms and diatom blooms, its a natural process.

What lights do you have and you should set these on a timer for about 8 hrs a day at this point :smile:

Shop Amazon

Shop Amazon
Shop Amazon; support TONMO!
Shop Amazon
We are a participant in the Amazon Services LLC Associates Program, an affiliate program designed to provide a means for us to earn fees by linking to Amazon and affiliated sites.