Sterling919

I've had a terrible problem with my fish all dying lately. I was treating with antibiotics for about a week now and today I did a 50% water change in my tank.

I removed four 5 gallon buckets of water, this is a 40g breeder tank. I replaced the water in my tank by connecting 1/2 hose to the vegetable sprayer of the kitchen sink, just removing the sprayer allows you to hook straight to the hose. I put the hose into the tank where it had the water running against the glass so no to disturb anything in the tank or splash and move the substrate.

Once I got it filled and got my filter going again and the powerhead I'm using for DIY CO2 injection, I noticed that just about everything in the tank looked like it had air bubbles coming off them. I assumed this was what I had read about called pearling. But what is pearling and what causes it? Is that what my plants were doing or was it from something else?

wyeto

Pearling is oxygen being released by your plants it looks like bubbles forming on the leaves usually. This sometimes happens to me after I do a water change and air bubbles get caught under them and it looks like pearling. They may have been pearling but that sounds just like what happens to me after water changes sometimes.

Sterling919

That is why I put the water back into the tank on one end in the corner. With a hose at low pressure and not making bubbles. So I will assume my plants were actually pearling then, now why do they do it? What causes them to do it?

bgzbgz

Pearling is what we call when plants use up the carbon from co2, and o2 is released.
What is more likely happening is the aerated tap water from your faucet has alot of air/oxygen disolved in it, which collects on plants fish, etc. Too much oxygen in the water can be bad for your fish, try putting some hydrogen peroxide in there, your plants will really start pearling and your fish too (bad idea dont actually do that).

BryceM

Yes.

Yes, pearling immediately after a waterchange isn't "real" pearling.

No. Not true. "Too much oxygen" is what causes pearling in the first place. Once the water becomes saturated (at least in the local vicinity of a particular plant) pearling occurs.

bgzbgz

I might be wrong here but I came to this conclusion from an experience a long time ago when I added faucet water to my tank. The water was obviously very saturated with air/oxygen, so much that I saw little air bubbles get stuck onto fish. Some of my clown loaches died within a few minutes. They started to produce insane amounts of slime coat which covered their gills and suffocated them. I am assuming this was caused by the microscpic air bubbles irritating their gills. I have actually read about similar things somewhere as well.

hoppycalif

Most likely adding tap water without using a dechlorinator, like Prime, caused the fish deaths. I have never seen a problem when I change 50% of the water in my 45 gallon tank, using tap water, and with Prime added at the beginning of the change. My fish always seem invigorated by the new water.

Tap water often contains some CO2, so right after adding a lot of tap water you may have more CO2 in your water than you usually do. That could cause the plants to grow faster for awhile, releasing O2 as they do so, and that is pearling. Fake pearling is easy to identify - the aquarium glass will be covered with bubbles, as will the hardscape and plants.

bgzbgz

I always add prime, im not trying to kill them lol.

NoSvOrAx

If fish die after a water change and you use prime, its probably temperature shock.