I would do a couple pretty decent water changes to freshen up the water as much as possible in anticipation for tiny tadpoles!!!
If you have a intake you need to get a pre filter sponge so you don't suck them into the impeller.
There is an Fluval Edge tank sponge prefilter which fits on most intakes for the HOB
filters and it is usually at Petco and I have seen at Petsmart but they have been changing around their suppliers so not positive but I think so still.
Added a link soa as not to have any confusion to what I was referring to for you and future readers.
EDGE Pre-filter Sponge | A1387 | Filter Media | Fluval
Not positive as to what they would want to eat but there was another thread the below section can't recall atm which, I think they would eat the Hikari Fry food First Bites but us it very sparingly, a little goes a long way. Try using the end of a tooth pick.
maybe through a prefilter sponge or with a net around it to keep from sucking them up or just use a cup and do a cup by cup removal checking for tadpoles as you go.
How fun, and how tiny.
Start looking for possilby an additional tank to start moving them ito as I imagine there will be a bunch an water quaility will be a concern with feeding.
After they get a bit bigger you might be able to try baby brine shrimp, which you might be able to find at a lfs
or SW lfs
frozen and slice off small amounts at a time.
As their mouths grow big enough they will probably eat about anything meaty based. I would try to vary foods as they grow up! Frozen foods will be a good resource but also pelleted foods to get them used to a captive diet in someones tank.
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