Danios and substrates

[sixtyfou]

I tried to explain this experience on another forum and failed. Let me try again.

I had about 7 Danios in a 10 gallon tank with standard gravel. I set up a separate breeding tank with marbles and the whole bit and that worked. I got a fry.

Then I noticed when I did a water change on the regular gravel bottom 10 gallon. If I saved the sludge in the bottom of the bucket in a glass I got fry that way too. This led to two thoughts:

1. Screw all that marble separate tank crap. These buggers can just be sucked out of the gravel.

2. When I'm not trying to breed them, the gravel is a poor substrate for Danios. They breed daily, and if they can't recover that protein it is bad. The trapped eggs that don't hatch will rot and decompose like uneaten food.

I'm thinking about adding a sand layer when I'm not trying to breed so the adult Danios can get to the eggs.

I know this sounds weird, but really these buggers lay eggs almost daily. You could never hope to save them all without a warehouse of tanks.

 

[hecurcia]

Imo, a 10 gallon is very small for keeping danios. Second, if you want to breed them, you should not put gravel on the bottom. Instead, a mesh should be put at the bottom with enough separation from the glass so the eggs can fall through. Once the danios made the dance, you remove them as they will eat the fry. The fry will not hide by nature, they will stick to the glass making them easy prey. Also, a sponge filter should be used.

 

[sixtyfou]

Dear forum, please read and stay on topic and don't tell me everything I can already read on the front page of Google.

The 10 gallon was a quarantine tank I had them in for a brief period of time while I made this observation. They are now happily living in a 30 gallon. Yes I know about the mesh. I know about the marbles. It all works the same. Now the question. "Does standard gravel act like mesh, or marbles?" My observation says it does. I think that might be bad. Should I act to correct it.

 

[hecurcia]

If you don't remove the adults they will eat either the eggs or the fry. The fry are stupid and it doesn't matter if hiding places exist. They will just swim out in the open. The only way to successfully breed them is to have all the tank for the fry. The eggs take 3 or so days to hatch, so there is plenty of time to wait and see if the female danio dropped the eggs.

 

[hecurcia]

I did not read the question very carefully. The answer, IMO is that it doesn't matter what you use (mesh, gravel, sand) when breeding them if you don't remove the adults or any other fish. None or very few will survive.

 

[sixtyfou]

What I'm asking is, "When I don't want to breed them. Is it a problem for those uneaten eggs to rot in the gravel?"

I've got more fry than I know what to do with at this point. I want the adults to eat the eggs now. My observation tells me they can't get to them easily on standard gravel. I want to add sand so the eggs are easy for the adults to eat, and don't become tank waste.

 

[hecurcia]

My glofish eat them just fine, on regular gravel or Eco complete. If you have unwanted fry, you can take them to your lfs. I had 6 on a 20 gallon and they did not reproduced as the adults went crazy for the eggs. I will occasionally see some fry at night but none will survive the next day. Experience vary for other fish keepers, on My experience it doesn't matter much as my fish are very egg hungry.

 

[sixtyfou]

Now we're on the same page. Try this, the next time you do big water change. Vac the gravel really good. Let the waste bucket sit for 3 days. You'll have a bucket full of fry. You'll also notice that a lot of the tank decay. Is old rotten eggs.

 

[hecurcia]

Now we're on the same page. Try this, the next time you do big water change. Vac the gravel really good. Let the waste bucket sit for 3 days. You'll have a bucket full of fry. You'll also notice that a lot of the tank decay. Is old rotten eggs.

I don't have to vac the gravel, i have a planted tank . Rotten eggs are not that big of a waste either.

 

[sixtyfou]

That's really the heart of my question. These Danios make more eggs than they make poop. I have to think that isn't good to be laying in your gravel. I'm going to plant this tank. It seems off to me. Clearly, it's not a big problem. I'm just considering best practices.

 

[hecurcia]

If you are worried about the amount of waste in the tank, a regular weekly cleaning routine will take care of it. You can't stop the female from dropping eggs all the time it is just nature.

 

[sixtyfou]

I'm thinking I should put a bit of sand over the gravel so the eggs don't fall into the gravel, and they'll get taken back up in the cycle.

 

[hecurcia]

Sure, it will easer to vacuum the surface of the sand and the fish can get the eggs easily. I particularly don't like a sandy bottom. It looks or gets dirty very quickly and if a fish splashes sand near the filter intake, it could ruin the impeller. But, a sand layer can be very useful for your goal of diminishing the egg waste.

 

[hecurcia]

Ah, you can't put sand over the gravel. it will fall through to the bottom sooner or later. You will have to replace the gravel for sand.

 

[sixtyfou]

I can't use a mix? I was thinking get some sand, put it on top. Expect it to mix. Eventually it would just be a sand gravel mix.

 

[hecurcia]

I can't use a mix? I was thinking get some sand, put it on top. Expect it to mix. Eventually it would just be a sand gravel mix.

I don't see what you couldn't use a mix. But I personally wouldn't like the look. A mix of gravel and sand doesn't add any benefit to the system except that it will be a quick "fix". And once both substrates are mixed, forget about separating them.

 

[sixtyfou]

Update: I've not been successful with this approach of breeding in the 20 gallon I moved the Danios to. I'm not sure if it's the tank volume, or the substrate, but I can't seem to suck out fry from this tank. I suspect it's that the gravel in the previous tank was more course and rounded. Which is funny, because it's the glo fish branded gravel. Funny/sad; the glo fish branded stuff is cruel to start with. What I'm suggesting is that it's really built to starve them out.