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Tetra Algaecides & Water Clarity
Related Articles & Questions
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- Vet Q & A
First fish tank: What Tetras and supplies for my 12-inch tank?
Before you buy any fish, you will need to set up the tank. A basic set up includes: a tank, filter, hood/light, heater, gravel and some decor. The tank should run without fish for at least 4 to 6 weeks. This gives it time to cycle. The Nitrogen Cycle is critical to the health of the tank and any fish you will be keeping. During this time, beneficial bacterial will populate the filter and substrate (gravel). These bacteria will be responsible for breaking down fish wastes and other wastes (uneaten food, dead plants, etc.). You will need a home test kit to monitor water chemistry (ammonia, nitrites, nitrates, pH) or you will have to submit water samples for testing. Most pet stores will do this for free or for a small fee. At first, you will see high levels of ammonia and nitrites. Over time, as bacteria grow, these levels will drop. When ammonia and nitrites are at 0 ppm and nitrates are below 20 ppm, you can consider adding fish. Regular (every 1 or 2 weeks) partial water changes as well as filter changes will be needed to maintain stable water chemistry and adequate water quality. The size of your tank will determine what fish and how many you will be able to keep. Most Tetras do best in groups, so a 12 inch tank may not be large enough. There are several article in the Petco Pet Education Center, formerly Petcoach Library that will provide more detailed information. Click on "Educational Center" at the top of the page, then scroll down to "Articles" and click. Use the Search Bar to find articles regarding aquarium set up and fish keeping.
Updated on September 24th, 2025
- Vet Q & A
Is algaecide safe for my fish tank? How do I remove tank algae?
There are different ways to control algae accumulation inside the tank: Limit the nitrate accumulation in it (regular water changes is the most common method of removing nitrate), limit the lighting period in the aquarium (4 hours a day) avoid overfeeding. Try Algone, very effective against nitrate, it is not an algaecide but it can control indirectly algae. If all these methods are not effective, algaecide are then needed.
Updated on September 24th, 2025
- Vet Q & A
My tank is cloudy and fish died. When can I add an Oscar?
If you put an Oscar in with your Tetras, they will be harassed and eventually eaten. Use a home test kit or submit a water sample for testing to check chemistry. Aim for 0 ppm ammonia and nitrites with a nitrate level of 20ppm or less. It can be slightly higher if you have live plants. If there is still ammonia present, the tank is still cycling. The cloudiness may be micro-bubbles which will eventually resolve or it could be a bacterial bloom which will also resolve once the tank has cycled.
Updated on September 24th, 2025
- Vet Q & A
Why are my fish dying fast with cloudy eyes? Is it water quality?
Thanks for reaching out about Diesel. This surely points to water quality issues. Have you tested the ammonia, nitrites and nitrates? Any chance of copper in the system? Parasites and bacteria rarely cause death this quickly. Remove all fish and place in new tanks, with spring water (bottled or reverse osmosis). Change or add carbon filtration. Good luck.
Updated on September 24th, 2025
- Health & Wellness
Why are my koi losing scales and goldfish have white head bumps?
This could be bacterial or parasitic infection. It is difficult to determine definitively since the image provided is not clear. Fish can be difficult to photograph. Basic care includes checking water quality and chemistry. This can be done using a home test kit or by submitting a water sample for testing. The local Petco may do this for free or for a small fee. There should be an absence of ammonia and nitrites with nitrates at 20-60 ppm. pH should be as close to 7 as possible, avoiding large swings. Koi can tolerate a wide range in temperature, but generally do best between 65 F and 75 F. Again, avoid large swings in temperature to prevent stress or shock. If necessary, a partial water change can be done to stabilize chemistry and/or improve water quality. If you have other koi, consider placing this one in a hospital tank to make treatment easier and to prevent spread if the condition is infectious. Plain aquarium salt (NOT table or Epsom salt) can be used to reduce stress, improve gill function, treat minor infection and aid in recovery. Dissolve 1 tablespoon per 5 gallons of water in a cup or two of tank water and gently pour it into the tank. Treat for 14 days then reassess the condition. If there is no change, consider a broad spectrum antibiotic or "all in one" treatment. Either can be found in the Aquarium section at Petco. Follow label directions carefully and remove the carbon filter insert during treatment if indicated. All that said, if the spots multiply and appear like tiny grains of salt, it could be an ich infection. In this case the entire tank will require treatment. There are several commercial ich medications that can be used. You will also need to thoroughly vacuum the substrate/gravel in the tank and wipe down all tank furniture.
Updated on September 24th, 2025
