Two questions I have:
1) how are you supplying CO2?
2) how long is your lighting period.
Just to specifiy, this type of algae is kinda jelly-like (not BGA).
1) CO2 tank, dual-gauge regulator at 15psi, needle valve. Tubing runs to Aquaclear HOB intake, where it is sucked in and smashed by the impeller. Using pH/KH method to determine ppm.
2) About 12 hours. Assumed that was ok since I consider it a low-light tank, but now I'm trying 8 hours.
It's definitely not BGA, or jelly-like. Small tufts of fine, uniformly short hairs. Soft and slimy to the touch but resilient. Scrubbing off the hairs leaves a GSA-like base which cannot be removed, and the hairs grow back from it. It resembles many algae, but exactly matches none.
I'm continuing to experiment. Will post if I find something that works. It would still be nice to know exactly what I'm dealing with though.
Have you figured out what is killing your zebra danios? They are a hearty fish (usually used to cycle tanks).
No, I haven't. They're actually red Glofish, zebra danios with a jellyfish gene spliced in for color. At this point I'm down from 40 in all my tanks to 5, and I'm not experimenting further.
I found a handful of reports of other people experiencing the same issue with regular zebra danios. Suspects were chlorine and pH/KH/temperature shock, but no definitive answers, and none that seem to apply in my case.
I have four tanks, and can move them between my tanks with no ill effects since I keep conditions very similar.
But if I perform a 50% or greater water change, they become stunned or paralyzed within a minute or two, and float to the surface. Any movement is twitchy and erratic. A few minutes later they are dead. Quickly moving the stunned ones to another tank that has not received a water change does not save them.
Here's the info on the three danio kills:
#1 - The 46g planted, but was using DIY CO2 at that time. Removed 50% water with Python. Added dechlorinator directly to tank, which was circulated by filters. Refilled. Added dilute muriatic acid to adjust pH for a target of 7.2 once DIY CO2 caught up. Assumed deaths were due to temperature change, or perhaps every danio somehow managed to swim through a cloud of acid.
#2 - 20g nonplanted. All livestock removed, 95% water change. Fill water was temperature matched to other tanks, and pH matched with muriatic acid. Water allowed to circulate for half a day. Moved in some guppies first, they were fine. Then moved danios, dead within minutes.
#3 - 46g planted again. At this point it's on pressurized CO2, and I am no longer using any muriatic acid for pH adjustment, the CO2 does it fine. I had added some danios a few days ago, the first time I put any in that tank since the original kill. Water change same as in kill #1, with the exception of muriatic acid; plus water was refilled very slowly, and carefully temperature matched. No signs of distress until tank was nearly full, then danio death occured rapidly as before.
