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Vet Q & A
Is it important to test my fish tank water's pH and other levels?
Yes, in order to have a healthy tank and to give your fish the best environment, it is necessary. Here is a good write-up on the reasons why: https://www.petcoach.co/article/water-chemistry-basics-ph-temperature-water-hardness-waste/
Updated on September 24th, 2025
Vet Q & A
Why do my fish keep dying in my newly set up aquarium?
It is possible the tank has not cycled properly which results in high ammonia and nitrite levels which can kill fish. Allow the tank to run, without fish, for at least 4-6 weeks. During this time, use a home test kit or submit a water sample for testing every few days. The local Petco may do this for free or for a small fee. What you are looking for is to have ammonia and nitrites at 0 ppm and nitrates at 20ppm or less. pH can hover around 7 for most community fish. Avoid large, rapid swings in pH though. What is happening in the tank during this time is that beneficial bacteria are populating the gravel/substrate and the filter. These bacterial populations are responsible for the Nitrogen Cycle. This cycle breaks down wastes from fish, uneaten food and plant matter into by-products that are filtered out or dissipate. You can "cycle" a tank with fish, however this increases the risk of loss. Once your tank has cycled, you can add fish. You will still need to monitor water chemistry and perform partial water changes regularly. Use only conditioned water that is temperature matched to prevent stress or shock. You will also need to vacuum the gravel regularly and rinse the filter media. Never use tap water to rinse. Use a bit of tank water to protect bacterial populations in the sponge.
Updated on September 24th, 2025
Health & Wellness
What's wrong with my emerald cory? Skin peeling, dark, sluggish.
Hi, and thanks for your question. Begin by submitting a water sample for quality testing. Most pet stores will do this for free or a nominal fee. Clinical examination should always include a water quality check, even if you have done so already. Water testing should be performed with a quality test kit, measuring NH4, NO2 and NO3. High ammonia levels, PH imbalances may be responsible for these signs. Oxygen concentration and quality of the filters should be determined as well. If water quality is good and there are no major imbalances, your fish should get examined to look for any sign of bacterial/fungal infection and eventually water should be treated. Hope this answer was helpful, but please do not hesitate to contact us again on the forum or by requesting a consultation if you have any more questions or to discuss it any further.
Updated on September 24th, 2025
Vet Q & A
Why are my angelfish and red tail shark sick in their new tank?
Check the water chemistry and temperature. Use a home test kit or submit a water sample to test fro elevated ammonia or nitrite levels. Most pet stores will do this for free or for a small fee. Partial water changes can be done, if indicated, to stabilize chemistry and improve or maintain water quality. Ideally, you want 0 ppm ammonia and nitrites with nitrates at 20 ppm or less in a non-planted tank or 40 ppm or less in a planted tank. Use only aged or conditioned water that is temperature matched to prevent stress or shock. You'll need to keep the temp at the upper limits for Red Tails in order to keep the Angelfish comfortable. That would be in the 78F to 80 F range. Both have similar pH requirements, 6.8 to 7.5. You can fast the Angel for 2-3 days then feed bits of cooked, shelled green peas. This will usually resolve constipation and bloating. Pristine water quality may resolve the patch on your shark. Recommending a medication without more information or a clear image would be risky to the stability of the tank's nitrogen cycle. You can use plain aquarium salt (NOT table or Epsom salt) as a general tonic. It will reduce stress, improve gill function, may treat minor infection and aid in recovery. Dissolve 1 tablespoon per 5 gallons of water in a cup of tank water and gently pour it into the tank. Treat for 10-14 days then reassess the condition. A note on tank size: Although the two fish may be fine in a 15 gallon tank now, you will likely need a larger tank as they mature. Red Tails can reach 6-7 inches and Angels can reach 6-8 inches. At adult size, a 15 gallon tank will be insufficient and could lead to some aggression from either fish.
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