550 gallons

[LizStreithorst]

After neglecting the fish for a week because of NADA, I did wipe downs and 600 gallons of water change yesterday.  I used every drop of my stored water.  They got another fresh 600 gallons today.  The fish don't appear to be any happier today than they were when I got home but I feel better.

Neither of my two groups of fry made it.  When I got home, their water was no longer green.  I can't figure out why.  There are some tadpoles swimming around in their tanks.  Do froggies eat fish fry?  I thought that they only liked insects.  Loosing the fry is not a great disappointment.   It was an experiment.  I gave them the best chance I could.

The 150 container that I set up for adult Dots and juvie Angels is packed with fish and they never skipped a beat.  All they have is 2 sponge filters  Their water is so green that I only see the fish when they come up for food or I do a huge.

[BillT]

At least some adult frogs can eat small fish.
Some tadpoles are entirely vegetarian, but some can carnivorous.
Some tadpoles have been studied for being cannibalistic on other tadpoles of the same species but which they are not siblings of.

[LizStreithorst]

I get that's what happened.  I tossed in a bunch of live CBW's and they are all gone, too.  Those tiny babies couldn't have eaten them all.  I bet it was a froggie.

What do you figured happened to the green water?  It was dark green when I left and light amber when I returned.

[BillT]

Mosquito larvae and Daphna are filter feeders. Got any of them in there? Or clams maybe.
I think tadpoles usually eat algae on the bottom not in suspension, but there may some exceptions that filter feed.

Might be lack of nutrients for the algae (nitrogen, phosphate, potassium and other stuff; fish poop should take care of that though), or light (seems unlikely since you probably had the lights on for the other tank).

[LizStreithorst]

It's too hot here for daphnia  to survive.  The tanks had no mosquito larvae in them.  There was sunlight which was strong in the afternoon.  Clams are not possible.   I threw a ton of BBS in the tanks before I left as well the live BBS.  Perhaps I should have tossed in some crushed flake to feed the aIgae.  I guess I will never know.  My feeling is that it had to do with frogs.

[BillT]

Baby brine shrimp are filter feeders.
However that is probably not a difference wrt the tanks which stayed green.
Dead or eaten baby brine shrimp are (or become) fertilizer.

Is the tank on a water system that automatically changes the water. It could have flushed out the green.