Do Algae Eaters Really Eat Algae?

About a month ago I bought an otosinclus algae eater for my tank because my tank was starting to grow algae. Hes been in there with my other fish but the algae doesn't seem to be decreasing.

(07-22-2012, 11:52 AM)mora2000 Wrote: About a month ago I bought an otosinclus algae eater for my tank because my tank was starting to grow algae. Hes been in there with my other fish but the algae doesn't seem to be decreasing.

Do you mean Otocinclus Catfish?
That is their name.

Otocinclus Catfish requires to be in a group of minimal 5~6. They are a school fish. Any less will make them under high stress and hide all the time, thus they won't be doing a good job eating algae.

What kind of algae are you having in your tank? Otocinclus catfish will only eat algae grow on the surface areas. They will also not touch hair algae, since their mouth is not built for it.

To get rid of algae, you must not relay on any algae eaters. They can only eat so much. You must go for the root problem. Excessive light, nitrate, phosphate, can cause algae boom. Limit the light exposure to no more than 8~10 hours a day, and decrease feeding, plus weekly partial water change of 30~50% will keep algae in check but not completely eliminated.

He is in there with 2 other fish. I'll see if I can get him some more tankmates. I have algae growing on the glass of my tank and the gravel. I know that he won't eat all of it, and I scrub some of it of during water changes.

(07-23-2012, 02:54 AM)mora2000 Wrote: He is in there with 2 other fish. I'll see if I can get him some more tankmates. I have algae growing on the glass of my tank and the gravel. I know that he won't eat all of it, and I scrub some of it of during water changes.

With 2 other fish isn't going to help.
School fish need to be in a group of their own species, and you need minimal 5~6 for Otocinclus Catfish.

You can't relay on fish to clean the glass for you.
The algae on the glass should be cleaned with an algae scraper. You can also use this kind of magnetic aquarium cleaner.

If you have lots of algae covering your gravel, then you must fix the cause. Is your fish tank near a window? Sunlight can cause algae boom, thus no fish tank should be near a window. We have covered this in an article about the location to set up an aquarium.

Do you have aquarium lights? How many hours do you turn it on every day? It is the best you use an automatic timer to turn the lights on for no more than 12 hours a day. (aim for 10 hours usually).

How often do you do water change? You have to lower nitrate through weekly water change.

I clean my tank weekly. The tank isn't near a window and the lights are on approx. 12 hours a day.

How much % of water do you change during the weekly tank maintenance?
20~30% should be minimal. Up to 50% is needed if there is excessive nitrate. The goal of partial water change is to lower the nitrate, phosphate, and other organic waste, at the same time to restore the water buffer and minerals.

How often and how much do you feed your fish?
You really need only need to feed once a day and no more than the fish can finish within a minute. Remove any leftover fish food immediately after feeding.

12 hours of lights a day is the absolutely maximum you should not exceed, but even 12 hours can be excessive if you are getting lots of algae. Lower the time to 10 or even 8 hours a day will help to control the algae. If it is needed, completely blackout of the tank for a few days can be used to reduce algae too. Fish don't really need the lights, there will only be negative effect if your tank is a planted aquarium.

Every change 25 percent of the water is taken out and replaced. All the fish are fed once a day, about a pinch of food at night.

Do you have a liquid test kit?
You might want to check your nitrate concentration. Try to keep nitrate below 20ppm, but always aim for lower the better.
If it is high, it can easily cause algae boom. If 25% water change doesn't do the job, you should always increase the % water change. Double it to 50% or do it twice a week. Light exposure should be lowered as well.

Algae eaters will never be able to completely wipe out algae unless there is very little algae to begin with.

I do have a water testing kit. I will check the water tomorrow since it is kind of late right now. Thanks for the help!

Hey mora. How is your test results?

I really hope you can increase the Otocinclus Catfish to at least 5. Once I ordered 6 of them, and they were really actively looking for algae everywhere in the tank. Two of them died much later one at a time. Once the number was down to 4, I stopped seeing them all together. They hid so well and I didn't see any of them for almost half a year until one time I moved a rock during cleaning. They just seem to get really nervous if they don't have the minimal required number in the same tank.

Nitrate in the tank is 20ppm.

I will go to the pet store today to see if I can take 4 home.

20ppm nitrate is very good, but since you have algae problem, you can always aim for 10ppm, or even below 5ppm. Increase your partial water change to a higher percentage will help.

Since you are going to get a few more oto catfish, the bio-load will increase, and it makes sense to increase the water change too.

Do not forget to quarantine your new fish if you have a quarantine tank. It is a great way to discover unwanted diseases or parasites before they can have a chance to infect your current fish.

Thanks. I will start doing 50 percent water changes.

Have you bought more Oto catfish yet?
Would you mind to show us a photo or video of your fish tank?

When I got to the store they had sold out . I am waiting until they get more in stock. I will see if I can take some good pictures of the tank with my camera soon.