Can algae be harmful to fish?

[willowthepoet]

I'm currently suffering the worst bout of algae I've ever had. My tank looks like a swamp despite daily 50% pwc. It's been completely green for almost 2 weeks and I'm getting horribly frustrated with changing the water all the time.

Today I found one of my ADFs up in the filter, dead. I started to worry if the algae was a symptom of some other problem? All my params are fine (0 ammonia, 0 nitrite, 5-10 nitrate because it's oh-so-slightly overstocked) and I'm completely out of ideas.

Help?

I'm tempted to put the fish in a bucket, clean everything completely, and restart the tank, hoping I don't lose my cycle... but my honey gouramis look like they're finally about to spawn (bubble nests everywhere) and an overhaul would almost definitely stop that.

[krap101]

for hair algae, it can clog up the filter. if you dont do anything and dont have any plants or anything..

sometimes when i got like mad at my tank, i left around 25% left in the tank and moved stuff around.

but algae itself shouldnt do anything bad. besides the visual

[tropicfishman]

As far as algea killing your fish, I don't think it will, I have heard of some air born bacteria that colors the water green, makes the water stink, etc. and it supposdly will kill your fish, I don't know the name if this bacteria I just heard a worker at a saltwater fish store talking about it to a customer...........sorry that was prolyl of no help to ya lol

[rippin17]

outside of buyign more algae eaters for the itme being or snails i dont kno what to tell ya but if its on the glass when mine go bad hair algae i scrapped the side of the tank and removed the loose algae with a brine shrimp net. ruined the net but it did the job. then i checked my phosphates, nitrates, nitrites. i also did the 48 hour black out method and everything worked out for me.

good luck!

[Wizzard~Of~Ozz]

If you are talking about green water, I had a congo die during an outbreak when I first set up my tank, not sure if it was related to the water or not.

If it is green water, throw a dark blanket over the tank and turn out the lights, (try to add an airstone or something if you can), then out go the lights for 5 days.. after the 5 days, take the blanket off, turn the lights back on (or 1 light if you have more then 1) and see if it's cleared, wait 30 mins from the time you turn the light on until you feed them. (otherwise you're feeding the bottom of the tank.)

[BrianNY]

Algae itself is harmless to fish. There are many factors that will cause algae to proliferate. Too much light and a nutrient imbalance are the most common. Dirty filters will contribute to the problem, so changing water without cleaning the filters isn't really a fix.

Green algae is a single cell algae and muct be completely eradicate. Running a diatom filter is a sure cure. See QTOFFERS thread on fixing this problem with diatom.

HTH

[malkore]

If you had massive algae, and then it massively died off, there could be an ammonia spike that'd harm fish. But that's indirectly causing harm.

Blue green algae/cyanobacteria can release toxins when it dies. However it's not actually algae, so does it really count?

[7Enigma]

Does your tap water have high ammonia, nitrIte, or nitrAtes? I'm wondering if the 50% PWC's are feeding the algae (though I don't know if algae use nitrAte as a nitrogen source) if you have high tap levels.

[willowthepoet]

ok... thanks everybody, i'll go through each post...

it's not hair algae. i've been scrubbing the sides of the tank, but it's all in the water.

it doesn't smell at all, so i don't think it's your bacteria... and i've seen that in my cousin's tank (at least i think it's what you're talking about) and that's a BRIGHT neon green, right? mine's dark and... well... swampy. definitely algae.

buying algae eaters won't help since it's in the water... and i don't want to put any more life in there anyway, since i'm slightly overstocked.

my tap water's fine... it has a tiny bit of ammonia, but i condition it with prime before it goes in the tank, so i doubt it's a problem. i've never gotten ammonia or nitrite in test on the tank, so i think that's fine.

i think i'll try the blackout thing for 2 days, then check it after that... i have an airstone, but my pump's real loud so i don't have it running right now. i'll go get one.

should i feed the fish during the blackout? wizard_of_ozz said he did it for 5 days, but i wouldn't want to starve my fish for that long! do you turn the light on for half an hour every couple days to feed them or would they be ok?

[Wizzard~Of~Ozz]

check it with low lighting (turn off all the lights at night, and shine a flashlight through the tank, you'll notice the difference)

also draining and filling the tank won't clear it up since it will be in the bucket and re-introduced.

Also from what I remember, it's caused by high phosphates and low Nitrates, water changes just feed the problem.

[Devilishturtles]

You say you have an airstone? How large is your tank, and is it filtered? Algae that is suspended in your water column can atleast be collected and filtered out through your filter (clumps of it, I mean, not the green water).

After you complete the black out, make sure you do a good water change. Dead algae is not good.

Also, I'd give it 3 days of the black out. No peeking, no feeding, no anything. The fish will be perfectly fine. You don't want light to creep in. If you want to go for longer, or don't feel comfortable leaving your fish for that long, then like Ozz said, use a flashlight to inspect the tank and feed if desired.

[willowthepoet]

ok... this is dumb, but where do high phosphates come from? tap water? how do you test for it? if i have it, how do i get rid of it?

yes, i have an airstone... it's a 29 gal tank with a cheapo whisper filter. (boo, i know) there's no clumps. i changed the filter cartridge before i started the blackout, but it didn't have any residue on it at all, so i don't think that was necessary. it's just really green water.

i still think i'll have to check it after 2 days and feed them. there's a pretty young angel in there and i don't want to risk losing it. i know i'm paranoid.

[Devilishturtles]

Not dumb at all.

High phosphates come from your tap water. To test for it, you'd have to buy a phosphate test kit. On how to get rid of it, there are phosphate reducing media you can buy for your filter that I've heard good news on, but have personally never used one.

As for the airstone, I didn't see you mention a filter, and was just making sure you have one that is moving around your water some. I have a whipser filter on one of my tanks that has lasted me years and years.

Not paranoid, just caring. I would be a little worried too if I were in your shoes. Make the trip inside minimal though.

Good luck.