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Learn how to pick the right aquarium plants, substrate, lighting, and fertilizers to ensure that your aquarium plants thrive and stay healthy.
Updated on November 13th, 2025
Discover care tips for marine aquatic plant macroalgae & the benefits of having macroalgae in your tank! Learn aquarium requirements, propagation, and mating facts.
Updated on November 13th, 2025
Learn how to use aquarium salt in freshwater aquariums to promote healthy gill functions, reduce stress, and treat infections in fish.
Updated on November 13th, 2025
Learn how to care for angelfish, recommended diet and aquarium setup. Find the right food, supplies and equipment at your neighborhood Petco.
Updated on November 13th, 2025
Acclimation helps your aquatic life adjust to the new chemistry of your tank, thereby helping ensure the health of your new addition.
Updated on November 13th, 2025
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 August 12th, 2025
Check the water chemistry first. Use a home test kit or submit a water sample for testing. The local pet store or fish store may do this for free or for a small fee. Aim for an absence (0 ppm) of ammonia and nitrites with a nitrate level of 20 ppm or less. Perform partial water changes as needed to stabilize chemistry and/or to improve water quality. Use only conditioned water that is temperature matched to prevent stress or shock. These fish produce a larger than average bio-load (wastes), so strong filtration is a necessity. The filter should be rated for at least twice the volume of the tank. The size of the tank may also be an issue. When keeping koi, tanks or ponds in the hundreds (or even thousands) of gallons are common. The number of fish in the current tank is too high. Consider getting multiple tanks or a significantly larger tank. 9 goldfish would need at least a 100 gallon tank. The additional koi increases this number.
Updated on August 12th, 2025
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 a
Updated on August 12th, 2025
Unfortunately this is a very generic sign and a radical approach must be followed in these cases to find the problem. Begin by submitting a water sample for quality testing. Most pet stores will do this for free or a nominal fee. High ammonia levels, PH imbalances may be responsible for that. Oxygen concentration and quality of the filters should be determined as well. If water quality is good and there are no major imbalances, your Fishy should examined to look for any sign of bacterial/fungal infection and eventually water should be treated. 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 August 12th, 2025
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 August 12th, 2025