Algae eaters compatible with discus?

[lag]

Have had to update my profile with the disastrous bleach episode. Have now got new 300 litre tank up and running and stocked with discus, angels, clown loaches and congo tetras. Everythings been looking fine until yesterday when the back wall became covered in green algae and the plants are all furry and some have brown rusty coloured algae. Having read other posts I think it may be due to keeping the light on all day and into the evening to marvel at my new Marlboro red discus. I will endeavour to keep the light down to a maximum 8 - 10 hours - is that the recommended? I see that you guys recommend Otocinclus, flying fox and chinese algae eaters - can any of these mix with discus. If I keep the light time down will the algae clear on it's own after a scrub? Don't think my one snail is earning his keep!!!!
PS: PH is neutral; nitrate is nearly nil (no such thing??); ammonia is nil; temp is 39 celsius

[AvoidLloyd]

I wouldn't recommend the chinese algae eater to go with discus. The flying fox might work, but at times they may be a little bit too boisterous for your discus. Otos would work fine. Another fish that could work well for you is the bristlenose pleco....they are voracious algae eaters which grow to only 6 inches, which is on the small side for a pleco. Usually bristles run around $15 at most LFS.

[vjvl51]

Hi Lag

The Chinese Algae eaters are known to attached themselves to the sides of fish. For this reason, I would not put them with discus.

I've had a Flying Fox and 4 otocinclus with my discus with no problems.

You say this is a "new 300 litre tank". If that is the case, then you have the cycle to go through. I found my discus very sensitive to water quality and I do not think that they would survive the cycle of a new tank - in fact I would not recommend adding discus until the tank is at least 6 months old. Normally you cycle a tank this size with 2 to 4 very hardy fish and then add the more sensitive fish where your ammonia and nitrites settle at 0. If you are in the cycle, then you don't have enough algae to break down the uneaten food down to nitrates quickly enough. Here is an article listing hardy freshwater fish http://www.aquariumpros.com/articles/fishcyclefw.shtml and here is an article on stocking your aquarium http://www.aquariumpros.com/articles/stockguide.shtml. If I have read this incorrectly, I do apoligize.

I convert your 300 litre tank to roughly 75 or 80 gallons. (I didn't look in my book for an accurate conversion.) Discus, when full grown require 8 to 10 gallons per fish. Angels have the same requirement. That means, between your angels and disus, you have taken up 50 gallons in your tank. Your clown loaches can grow to about 6 inches in an aquarium, so there is another 12 gallons. The 5 congo tetras will grow to 2 to 3 inches each, which requires another 10 gallons. Total gallons required is 72 when all your fish are full grown. Your tank, IMO, is very close to maximum bio-load so you shouldn't add many more fish.

Snails are debris cleaners and don't do much for algae that is already growing. By eating the left over food, they help to prevent algae from growing.

There are two main things that allow algae to grow - light and nutrients. You will be cutting down on the time that the light is on. That can be good and bad. More about this later.

I have had better luck, controling algae by planting fast growing plants that use up the nutrients before the alage can. I keep a partial cover of crystal wort (a floating plant) on my tanks because it grows quickly and is easy to remove the excess (just reach in and take out handfuls.) I also have many plants growing in the tank to help use up the nutrients. For any plant to grow quickly (and you need quick growth to use up the maximum nutrients) you need lots of light. This is why cutting down on your light can be bad. Cutting back on the hours the light is on is one thing but ensure that when the light is on, there is enough light so that the plants can grow quickly. I have two full-length fluorescent bulbs on each of my aquariums to get enough light for the live plants to grow.

Some people cut back on the feeding to control the algae. I do not recommend that as discus are what I call browsers. They like to leisurely pick at the food over a hour or so. Depending upon how much you cut back, you can affect not only their size but also their health.

Vickie

[lag]

Thanks
The tank is 5 ' - at the moment I have two 4' PowerGlo tubes running. Different people have told me I may need more - what do you think? ( I was also told I could keep 8 discus plus at least 5 angels - obviously way too many on your opinion)

[Nooboon]

Hi Lisa,

As everyone has said, chinese algae eaters are bad news, they don't eat much algae anyway. Simease flying foxes eat more algae than regular flying foxes but don't look as pretty in my opinion. I would say you would be safe with the otos though.

I would agree with vickie about the stocking rates. You could add a few more fish, but don't get carried away. Sometimes overstocked tanks do fine but if something goes wrong it usually happens in a big way.
I looked at your profile and it says eheim professional filter. If it is the 2026 I would be very cautious not to add to many more fish, the 2028 would give you a little more room for error.

As for your lighting, I would stick with 12 hours a day. If you are away during the day and want to look at your fish in the evening, get an auto timer to turn the lights on at 10 am while you are out and off again at 10pm. You won't get to see much in the morning though.
If you want to grow some good plants, I would add a couple more lighting tubes. Up to you though.

As for the algae; as Vickie said, algae needs light AND nutrients. I used to have a few algae problems but over the last few years I have surprised myself at how much less growth I have by limiting the nutrients in the tank (namely nitrate and phosphate - I still fertilize my plants). Regular water changes, not using carbon (known to leach phosphates and remove important trace minerals), a good filter system (more than twice the recommended size), and plenty of live plants keep levels way down. I have taken to feeding algae wafers at least every second night because I am concerned for my algae eating fish.
I would imagine that if you measured nitrate and phosphate levels in your tank you would find the up a bit.

If you do decrease the lighting period substantially, be aware that the algae may die from lack of light but then the decomposing algae may cause other problems. It would be better to decrease the lighting period slowly over a week or so.

[vjvl51]

Lag, people are probably quoting the "rule of thumb" of 1 inch of fish per gallon. That works in most cases except when you have to consider territory requirements (for cichlids - angels and discus are South American cichlids) and unusually shaped fish (like these). For discus and angels, the rule of thumb is 8 to 10 gallons per fish. Discus, in particular are known for secreting a growth hormone that will limit the size of all other fish in the tank. If you want the your disucs to reach full size, you have to allow 10 gallons per fish AND do partial water changes weekly. (This is something that I have recently found out.)

Another thing to consider is that the higher the temperature the lower the amount of oxygen the water can hold. Discus require a temperature of at least 80F.

You can put more than the recommended fish in your tank as long as you accept the consequences. My 75 gallon was slightly overstocked and I didn't get at the partial water change and filter maintenance when I should have. The result was a crash. Since I was late on the water change and filter maintenance, the oxygen level went too low and one discus died. Because the temperature is so high, it started to decompose fairly quickly and contaminated the water which resulted in the other discuses dieing and so on. This all happened in the space of about 6 hours one night.

As per your lights - I would say look at your plants. If you have some plants that are not growing or are slowly dieing, then you will need more lights. If the plants that you have are growing and producing side shoots, then you have enough lighting. This is a balancing act with discus as they prefer a darker aquarium so you have to provide plenty of plants to give them shaded areas to go to.

Vickie