I have had fish tanks my entire life. Generally, goldfish are messier than tropical fish, and the tank needs more frequent filter changes. However since ive been using this product there is a noticle difference in how much cleaner the tank stays as well as filter changes are mich leas frequent. I do a 1/3 water change and vaccum the gravel once a week. Follow directions for dosage during water change.This product is great. It always makes my tank super clean. I like that you can add more or less depending on how dirty your tank is and it gets even the dirtiest tank Crystal clear clean. Very happy with this product.Too smallUse this as a very common thing in my tanks to help clean them. Easy to useHad no effect on my tankHad an issue with cloudy water . Follow directions worked pretty good to clear water in tankI like this productThis stuff really works - I have three very large fish and this works wonders in reducing the amount of waste in the tank - fish seem to really like it too!It would be nice if it were sold in a larger container as with the size of my tank, it doesn't last too long but I really wouldn't be without it.Helps with the water slightly but tank still goes green quickIt works okay...doesn't last a week.. new goldfish owner having adding a few baby ones that are settling every week there's often a lot of poop bit not everything dissolves after like 4 days. ..cleaning tank once a week anyway so it's not badDoes exactly what the label says. Definitely recommendDoes what it says and definitely keeps the tank clean. Will but again.