My fish suddenly died tonight

Daltrey · Jan 5, 2018

On my 40 breeder I always have the powerhead pointing up at an angle. It creates lots of surface agitation that helps to get more oxygen into the water. On my large tank my skimmer is plumbed to draw fresh oxygen from outside.

The only pic I have on my phone right now but if you could see a video the water flow is very strong at the surface.

Katrina71 · Jan 5, 2018

Oxygen test kit? I had no idea they even made that. I would like to test mine too. Just for the sake of learning. If I lived closer, I'd be showing up today with cookies and a pair of clowns. Lol. Hey, what are friends for?

rkpetersen · Jan 5, 2018

TikiBird said:
I’m thinking maybe I will get a dissolved oxygen test kit. I don’t know if the reading would mean anything now, but it might tell me something.

I did notice when I would occasionally put an airstone in the tank, the fish would be more active and lively. I was actually considering putting one in all the time because they liked playing with the bubbles, but I hadn’t gotten around to it yet.

Their activeness with the bubbler makes me wonder if I didn’t ever have enough gas exchange going on with my cube.

Edit to add: I’m not saying that there was some kind of massive oxygen disaster that killed them necessarily, but it might have just been a combination of smaller mistakes that added up, one of which was maybe long-term not enough oxygen...? It’ll be something to test for at least.

Fish are definitely known to hover around air bubble columns when the O2 is low. Also, they will hover near the water surface at the top. Often, they will seem to be gulping/gasping air from the surface. Of course all of this should be accompanied by fairly obvious distress and rapid gill movement.

Adding another small powerhead or air bubbler is never a bad idea. But a protein skimmer is a better addition than either. Even a small unobtrusive hang-on-back skimmer would probably help a lot.

Regarding testing for dissolved oxygen - It's of little value on a regular basis on a tank that's running well, as the value should always read around 6 ppm or slightly higher. In your case, it might be educational, but your money would be better spent on adding a skimmer. I would not get the Salifert O2 test kit; although inexpensive, it's resolution is too low to be of any real value. If you do want to go ahead with measuring your DO, the kit to use is by Lamotte. This kit has been around for decades, virtually unchanged (I used it in the late 80s), and is one of the highest quality hobbyist test kits available from any company.

There are also oxygen probe/meter systems available but these are quite expensive and not necessarily more accurate than the Lamotte kit. They do provide ongoing real-time monitoring and can also record data for review later.

TikiBird · Jan 6, 2018

Daltrey said:
On my 40 breeder I always have the powerhead pointing up at an angle. It creates lots of surface agitation that helps to get more oxygen into the water. On my large tank my skimmer is plumbed to draw fresh oxygen from outside.

The only pic I have on my phone right now but if you could see a video the water flow is very strong at the surface.

Ah yes. I have always wondered if my surface agitation is too low. I have the return nozzle pointed up but even so it doesn’t seem strong. I actually got a Turbelle Nanostream for Christmas but I hadn’t installed it yet. [emoji20] I do need to use a skimmer.

TikiBird · Jan 6, 2018

rkpetersen said:
Fish are definitely known to hover around air bubble columns when the O2 is low. Also, they will hover near the water surface at the top. Often, they will seem to be gulping/gasping air from the surface. Of course all of this should be accompanied by fairly obvious distress and rapid gill movement.

Adding another small powerhead or air bubbler is never a bad idea. But a protein skimmer is a better addition than either. Even a small unobtrusive hang-on-back skimmer would probably help a lot.

Regarding testing for dissolved oxygen - It's of little value on a regular basis on a tank that's running well, as the value should always read around 6 ppm or slightly higher. In your case, it might be educational, but your money would be better spent on adding a skimmer. I would not get the Salifert O2 test kit; although inexpensive, it's resolution is too low to be of any real value. If you do want to go ahead with measuring your DO, the kit to use is by Lamotte. This kit has been around for decades, virtually unchanged (I used it in the late 80s), and is one of the highest quality hobbyist test kits available from any company.

There are also oxygen probe/meter systems available but these are quite expensive and not necessarily more accurate than the Lamotte kit. They do provide ongoing real-time monitoring and can also record data for review later.

Ahh yes I think a skimmer is a must now. I already ordered the dang Salifert kit, darn it. I’ll see what it says for kicks. Lol If I know I’ll recommit to this, I think I’ll get the Lamotte. It would probably be good to know and check on once in a while. I’ve always wondered if the BioCubes are more susceptible to lower oxygen because they’re all sealed up. But I have no idea.

TikiBird · Jan 6, 2018

Katrina71 said:
Oxygen test kit? I had no idea they even made that. I would like to test mine too. Just for the sake of learning. If I lived closer, I'd be showing up today with cookies and a pair of clowns. Lol. Hey, what are friends for?

Thanks lady. It never occurred to me to see if they made oxygen test kits until yesterday.

No clowns for me yet though! I’m still not sure I want to take the plunge again. But I will take the cookies. [emoji23]

kevyg · Jan 6, 2018

You are going to recommit. You didn't have a crash and lose thousands of dollars in stock. You got into this amazing hobby to see the best critters, but nature happens and that is the learning curve. I'm with Katrina, don't hymn and haw and be a victim in this. Tell yourself " I am going to figure out the death, fix it and make sure I don't do this again. I would say take as long as you can to look into the death but knowing you are GOING to bounce back.

If it is a matter of the tank not being something you liked having to maintain, that is a different story, and if that is the case, then your son might be right.

She gave the mom, I gave the harsh dad.

I'm not insensitive, but I do want discourage self defeat.

Lasse · Jan 6, 2018

If you will use an oxygen test kit - take the measure just before daylight (or just before the main light goes on) The oxygen level will be lowest at that moment. And that´s the only thing you need to know. The lowest point. A normal aquarium with a skimmer normally have a swing around 20 % depending on light regime.

Sincerely Lasse

TikiBird · Jan 7, 2018

Lasse said:
If you will use an oxygen test kit - take the measure just before daylight (or just before the main light goes on) The oxygen level will be lowest at that moment. And that´s the only thing you need to know. The lowest point. A normal aquarium with a skimmer normally have a swing around 20 % depending on light regime.

Sincerely Lasse

Oh interesting! I will definitely remember to do that.

TikiBird · Jan 7, 2018

kevyg said:
You are going to recommit. You didn't have a crash and lose thousands of dollars in stock. You got into this amazing hobby to see the best critters, but nature happens and that is the learning curve. I'm with Katrina, don't hymn and haw and be a victim in this. Tell yourself " I am going to figure out the death, fix it and make sure I don't do this again. I would say take as long as you can to look into the death but knowing you are GOING to bounce back.

If it is a matter of the tank not being something you liked having to maintain, that is a different story, and if that is the case, then your son might be right.

She gave the mom, I gave the harsh dad.

I'm not insensitive, but I do want discourage self defeat.

Haha! Thanks @kevyg. I totally get that and I appreciate the kick in the pants. lol

Lasse · Jan 7, 2018

Thanks

I have removed my first text in this post because I was angry about a rude post
The post I argue against have been taken away by the mods - @jsker - you can take away this post too

Sincerely Lasse

don_chuwish · Jan 7, 2018

Lasse said:
Thanks

I have removed my first text in this post because I was angry about a rude post
The post I argue against have been taken away by the mods - @jsker - you can take away this post too

Sincerely Lasse

Good job mods!

TikiBird · Jan 11, 2018

Lasse said:
If you will use an oxygen test kit - take the measure just before daylight (or just before the main light goes on) The oxygen level will be lowest at that moment. And that´s the only thing you need to know. The lowest point. A normal aquarium with a skimmer normally have a swing around 20 % depending on light regime.

Sincerely Lasse

Just an update: tested my water this morning (got up early and everything! lol) and it reads on the Salifert kit a little darker than 6. (Although I know it’s not super accurate.) That’s at 78 degrees and before sunrise.

40B Knasty · Jan 11, 2018

Is there such a thing as to much O²?
Is there a good range to be between?
I always wanted to know this to really get a better understanding with pH, CO², & O² to help catch my weak point of the day and see if it could be beafed up. Also to help with my GHA management.

Lasse · Jan 11, 2018

At 77 degree F. 34,5 psu and at sea level - 100% saturation is around 6.74 mg/l - 5.9 mg/l is around 75 % saturation - should not be anything to worry about.
Calculator

Sincerely Lasse

rkpetersen · Jan 11, 2018

40B Knasty said:
Is there such a thing as to much O²?
Is there a good range to be between?
.

With strong illumination, lots of algae growth, a trickle filter with air pumped into it, and a good skimmer, you can achieve mild oxygen supersaturation conditions in a reef tank. This is safe and generally beneficial to your animals, but on the other hand, not at all necessary to have a successful reef (and nobody uses trickle filters anymore, anyway.) Dangerous oxygen supersaturation, which can actually hurt fish and other animals, is highly unlikely with systems and techniques typically used by hobbyists, although I believe a weir might be able to cause this if used incorrectly.

Use of ozone, by the way, does not increase your dissolved oxygen levels directly. It may help to do so indirectly, by oxidizing dissolved organic compounds which would otherwise use oxygen to decompose.

Lasse · Jan 12, 2018

A rather good equipment - maybe not so common in the US - is the oxydator. I do not know if this company is still in operation but it gives a rather good description of the products. Otherwise - google on "oxydator sochting". It has some other good effects too. I use one in my aquaria. Many freshwater shrimp breeders use them in order to maintain a good O2 level during night.

Sincerely Lasse

Katrina71 · Jan 12, 2018

Lasse said:
A rather good equipment - maybe not so common in the US - is the oxydator. I do not know if this company is still in operation but it gives a rather good description of the products. Otherwise - google on "oxydator sochting". It has some other good effects too. I use one in my aquaria. Many freshwater shrimp breeders use them in order to maintain a good O2 level during night.

Sincerely Lasse

Apparently this is popular in other countries. I'm curious.