Tropical fish tank...............25 gallons.................When cleaning out the tank tod

[lilacben]

in the container the dirty water was in my granddaughter noticed there was black tiny things swimming around. And when my husband tipped it into the sink you could also see tiny white worms and some coloured ones. We havent got any new fish in there. Is there anything we should do.? Many thanks

[paddywak]

Don't know about a tank but in ponds you always find worms and things in the filters etc and when you clean them out you always leave some of the old water, dirt, worms etc in the system as they actually form part of the filtration cycle and if you clean them all out it takes longer for the system to get back to normal as the biological side has to start from scratch.

[wildwood]

It might have been a good idea to take these worms to a fish shop for IDing. Not knowing what fish there were in the tank makes it hard, but it could have been baby black mollies.

The dirty water... did you also uplift and clean the gravel? The worms could have been part of food your grandaughter fed, maybe tubifex?
(before someone shots me, I am not suggesting to clean the gravel)

[lilacben]

Thankyou for replies. My husband lifted the gravel up when he syphoned it this afternoon. We had never noticed these things before. It was just that our granddaughter was here and the dirty water was at her eye level. They could have been there all the time and we hadnt noticed them. They was very tiny black dots.very much like the flour weevils you get. Most of my fish are fan tail guppies and neons. plus my white/pink gummy as I call him. the fish that eats all the left overs.

[divegirl]

Hi, sounds like you have planaria worms which are caused by over feeding. From memory I can't remember how they get in there but they are easy enough to get rid of, give all the substrate a good wash, a large water change but leave the filter [you want to keep your good bacteria].
You could try adding a couple of tsps of Aquarium salt, 1 tsp for every 5 gallons should do the trick.

Lisa x

[divegirl]

Thats flat teaspoons by the way.