View Full Version : water changes and fry

fish speaker
02-28-2005, 09:26 PM
I have read numerous posts emphasizing the importance of water changes in fry tanks. I have a couple of tanks that suddenly have fry, and I have a practical question. One of the tanks has a cloud of tiny fry, newly free-swimming. The other tank has fewer, slightly larger fry. In neither case do I trust myself to be able to see where the fry are while trying to change water, so my inclination is to avoid the area in the tank where the fry are concentrated until they are a little larger. If this is a bad idea (which it might be, since I have also seen at least one post that makes it clear that the vacuuming is the important part), how would you recommend vacuuming out the debris while minimizing fry mortality?

Thanks for any recommendations. I'm too tired tonight to do these tanks, but will definitely do them tomorrow.


02-28-2005, 09:58 PM
A few quick movements of the hose usually sends mine heading for cover. They're usually on the opposite side of the tank from where I vacuum. The bare bottom makes it easier to vacuum though and the current usually deposits all of the detritus on one half of the tank.

02-28-2005, 11:51 PM
i had the same concern when there were fry in my tank, but like Owasso said they move out of the way of the syphon before it gets close to them.:)

03-01-2005, 03:14 AM
...well, most fry will get out of the way of the siphon...but my calvus fry sure dont...they head straight for the bottom and cover most of the bottom of a 20 long...they seem to find more comfort in the spaces between the pool filter sand (pfs) than in the pots or shells....this has made gravel vacking impossible for me in this tank...I think having substrate in a calvus fry growing out tank is a bad idea, and in retrospect I would not have put them in a tank with substrate...while this has yet to cause any water quality issues, I am concerned about long term build up as these guys are notoriously slow growers...my hope is that as they mature they will become more free swimming and prefer the caves to the substrate when the Python gets near them....

Next brood is going in a bare bottom tank...

fish speaker
03-01-2005, 08:30 AM
Thanks for the tips. I'll give it a try tonight. One of the tanks will be more difficult than the other: I have a huge number of very small Thorichthys aureus albino fry. They are free swimming, but they are tough to spot against the substrate (they are with the parents in a tank with a sand substrate). The other tank should be easier: mbuna that are slightly larger than the thorichthys, and in a bare-bottom tank. Of course, their parents in the main tank don't fear anything that I put in the tank, so I'm hoping that the fry will not be as bold as the parents.


03-01-2005, 01:53 PM
I only do heavy water changes with fry only barebottom tanks. If they're with the parents then i just do normal maintanene. You could just siphon the water into a bucket, then check the bucket to see if there are any babies in there.

fish speaker
03-01-2005, 09:53 PM
I did a normal water change in the thorichthys tank (parents still managing the fry). I kept away from the cloud of fry, since they collectively didn't seem to recognize the threat of the intruder. I followed up with an unnecessary scraping of the glass, and the parents acted like a midas: they charged the scraper, gills flaring...quite the show. I guess I'll just let the algae grow for a while, to keep from freaking out the parents. By comparison, the mbuna/vic fry were easy to clean around.

03-03-2005, 11:13 AM
I also leave the algae alone when there are babies in a tank. I notice they like to graze on the algae.