Questions for successful egg-laying fish breeders...

[bs6749]

What do you use to get rid of any fungus or harmful bacteria in your grow out/spawning tanks? Hydrogen peroxide, pimafix, melafix, and methyl blue (also methylene blue) are fairly common to use, so what have you personally had success with? I am trying to get rid of this in my grow out tank in which I am trying to raise GBR fry. First here are some things you should take into account about the tank itself:

10 gallons, pH roughly 7.2, temp about 82, all of the water in this ten gallon tank was taken from the main 55 gallon tank which itself was over 95% RO water that will be two weeks "old" this Monday. I put in some pool filter sand that was from the 55 gallon tank (seeded material for the cycle) and I put some java moss in there as well as all of my spare pieces of slate.

Any help would be greatly appreciated as I would really like to get these wonderful fish to successfully breed. Yes, I have tried keeping the eggs with the parents and they just seem to eat them.

[rich311k]

I moved this to the breeding section where it belongs.

[bs6749]

I was hoping that it wouldn't get moved as I thought it might get more responses but I guess it should go here.

[Gillie]

I use malachite green.

[BrianNY]

As long as fertilization is succesful, you don't really need a fungicide. A small airstone to create a gentle water movement near the eggs will do the trick.

[Jchillin]

You may want to follow this thread. It looks pretty promising.

[bs6749]

rwhayley - I have never heard of malachite green before. Where would I start to look for it? Is it an anti fungal agent? Are there any pros/cons with using it? What type of fish eggs have you successfully used it with?

BrianNY - Are you saying that fertilized eggs are in some way less succeptible to fungusing than non fertilized eggs? I guess I should have placed an airstone in the tank as well like I have done before... for some reason I was thinking that the sponge filter would create a current. I don't know why I was thinking that because the air basically goes in and comes back out the top of the filter.

Jchillin - Thanks for the link. I will keep checking on it.

I have noticed with some of my previous attempts at GBR fry that eggs seem to fungus rather easily. I have also noticed that the addition of small quantities of egg yolk (when the fry are large enough to eat it) seem to fungus as well. The yolk will have growth on it in about a day or so, I just don't feel that it is healthy for the tank/tank inhabitants.

[BrianNY]

An egg that hasn't been fertilized will surely fungus. The reason to have a gentle water current near the eggs is to prevent any debris from clinging to the eggs. This is why egg guarding parents fan their eggs. Anything which collects on the eggs will also kill them.

If the eggs are layed in a spot where they are visible, any eggs which are not developing can be removed with tweezers. Failure to do this will spread fungus to developing eggs.

[bs6749]

It is difficult for me to tell which eggs are not developing with my rams because the eggs are so small and they tend to hatch in 36 hours or so. I have tried to remove the bad ones before and did so with moderate success. Now I try to leave the eggs with the parents as long as possible because they will pick the bad ones out for me and then I move them to the grow out tank to try and maximize the survival rate.

Just a general question for you BrianNY... I know that you are into discus so I assume that you have bred them as well (could be wrong), what temp do you keep the water at? Warmer is generally better right? I was thinking 84 degrees would be okay. Is this too high or too low?

[BrianNY]

84 is ideal for discus. I drop the temp to 80 to induce spawning. I've never spawned GBRs but would think it would be similar to discus.