How to prevent fungus on Angelfish eggs?

[marinkitagawa]

My pair of Angelfish just laid their third batch of eggs on a slate, but like the previous times, the eggs turned white and fuzzy within 48 hours. I suspect it's a fungus issue. Should I be using Methylene Blue to treat the water, or is it a matter of improving the water flow around the eggs? Any tips on keeping the batch healthy until they hatch would be appreciated.

 

[skjl47]

Hello; I had a breeding pair who laid on live plant leaves. The parents ate the eggs, so I started clipping the leaf and putting it with the eggs in another tank. The 2nd tank was bare and clean. I set up a bubbler (air stone) so the bubbles were close to the eggs. Weighed down the stem with a bit of lead wire which was commonly used to bunch plants decades ago.
I did add some methylene blue into the water with the eggs. I raised a few batches of fry. I figure the methylene blue helped. I made a thread of the experience on here. Do not know if it still is around.

A question or two arise. I would be cautious about adding the blue dye to an established ongoing tank. If you are fortunate to have a pair who do not eat the eggs/fry I would hold off to see if the pair can learn to keep them clean. Another concern is the dye is permanent and will stain stuff in the tank. The stain also attaches to organic material in the tank.

Another question is are the eggs actually being fertilized? I usually had a few eggs turn white but not all. Might be the parents are not quite good at it just yet. You can expect a breeding pair to spawn again and again. I suspect it depends on how long it takes the female to make a load of eggs. Roughly three weeks to a month in my case.

I might try a couple of things were I to be in your situation. Set up an empty tank and be ready to move the slate right away. If that works you will have some other things to consider. I was lucky to have a mature sponge filter in another tank. After the fry hatched, I added the mature sponge filter rather than use an impeller HOB. I was concerned the fry would be sucked into the intake. To my pleasure the fry at one point began to graze on the sponge filter. Eventually cleaning the surface down to the sponge.

One note of caution. Keep an eye on the male from now on. My female was very aggressive and eventually damaged the male. I caught the injuries too late and even though I moved him & treated the wounds he died. The male did not try to get away from the female. Instinct, I guess.

Good luck.

 

[jjohnwm]

Another question is are the eggs actually being fertilized? I usually had a few eggs turn white but not all.

I tend to suspect this might be the case here. I'm not a cichlid guy as such, but I've had a fair number of cichlid species spawn in my tanks over the years. I expect a certain small number of eggs in most clutches to fungus within a day or two, and if the parents don't remove them I usually do. But when an entire clutch turns up white and dead, it points to a lack of a fertile male...or even to a lack of any male at all. It's not that uncommon for a lone female fish to lay a bunch of duds, or for two females to appear to be a breeding pair when in fact they are just good friends.

Many years ago I had a "pair" of Uarus who spawned like clockwork every couple months. Never once hatched an egg. The hobbyist from whom I got them had the same problem and eventually just gave up on them, which is how I came to own them. One day I was fortunate enough to be on hand when they spawned; imagine my shock and surprise when both fish proceeded to lay eggs simultaneously. Not sure how they self-identified...that wasn't a "thing" back then...

Both of those fish went on to lay and hatch healthy eggs after I eventually got more Uarus, including some fertile males.

Have you actually witnessed a spawning? Or do eggs just seem to appear by surprise?

 

[marinkitagawa]

Thanks for the insights, everyone!

I haven't actually witnessed the spawning process from start to finish; the eggs usually just appear on the slate. After reading your comments I’m now wondering if I actually have a fertile male or if I might have two females acting as a pair

A couple of follow-up questions:

1. If I decide to use Methylene Blue, is it safe to dose the main tank, or should I move the slate to a separate hatching container to avoid staining?
2. What’s the best way to confirm I have a fertile male? Should I look for specific behavior or physical signs during the next spawn?

I'd appreciate any advice on how to troubleshoot this further!

 

[phreeflow]

1) adding a little methylene blue won’t hurt your tank but it’s an oxidizer so too much and you’ll kill off your beneficial bacteria. Also, it’s not needed if your pair is fanning the eggs. Like John said, they’re most likely unfertilized. Also, as a side note, do not add more flow…doing so may result in the eggs not getting fertilized as it will blow the male’s milt away when they’re breeding. You can take the slate and put it into another tank AFTER they breed and add flow but during before

2) Look to see which one is laying the eggs. Also look at the genital papilla or egg tube when they’re in breeding mode and the male’s will be long and thin and the female’s will be short and wide

 

[skjl47]

If I decide to use Methylene Blue, is it safe to dose the main tank,

methylene blue won’t hurt your tank but it’s an oxidizer so too much and you’ll kill off your beneficial bacteria.

Hello; You can add but I would not if the purpose is to try to save the eggs from fungus.