Nitrates levels too high?

I'm suprised that after 4 months with only 3 platies that you are still having nitrate problems. If you didn't just recently add the fish, there is a good chance you are feeding them too much. I would cut back on how much you feed them (only once a day, and only what they can eat before it sinks or what they can eat in 3 minutes, whichever comes first) and start doing 20% water changes every 1-2 days. As for the algae bloom, turn of the aquarium light and make sure it isn't getting direct sunlight from a window. Leave it without light for a few days to a week, and then when you do turn the light on, cut back on the amount of time the light is on (if it is on more than 8 hours, cut back to 8 hours, if it is on 8 hours or less, cut the time by an hour). This will help prevent more algae from growing. Also, platies like salt, so if you don't already keep salt in the aquarium, you can add 1-2 tbsp of aquarium salt to reduce stress on the fish while you are dealing with the nitrate problem. Once nitrates are under control, you may want to invest in an algae eating fish. Do research into the type of algae you have and get something that prefers to eat that type. I would suggest oto cats, siamese algae eaters, or shrimp, but stay away from plecos as they can be destructive and aggressive and will also outgrow your tank.

Water changes, water changes and more water changes. Don't ever add chemicals to the tank, the less you mess with stuff like that the better. Only having 3 platies in a 10 gallon you shouldn't be having a problem with the nitrates unless you are over feeding them. Live plants will work but if you are like me they won't last very long, try feeding them half of what you are feeding now and see if that helps. And if you don't have a gravel vac then get one, they not only clean all the poo and other debris from the gravel but they make water changes a lot easier.

You need to siphon the tank. This vacuums the bottom of the tank and cleans the bad things that cause algea to bloom on the bottom. You can also buy a product at you local pet store that brings these levels down, but without a 20% water change and siphon, it will return shortly after. You only need to do a 20% water change at the most, or it could cause algea to bloom. You also have to make sure the tank is to where it does not get direct sun light. If it does this is another cause of the algea.

Add plants first. LOTS of plants will suck up the nitrates and edge out the algae. Before adding clean the algae by hand. Upgrading to a bigger tank at least 2 feet will do wonders. Small tanks are hard to upkeep with more water changes and faster spread of disease. a dead fish in a small 1 foot tank will kill off water quality even but in a 2-3 footer will not do that much damage as fast. Also consider the fact that your filter is ineffective.

a severe point in something in a fishtank is risky. that why people circulate on approximately working a tank with out fish for some weeks while its newly set up. how massive replaced into the water substitute? in case you have biggish fish, you are able to injury out with a nil.5 tank water substitute with out genuine repercussions. i could be at risk of do yet another water substitute, then see what the fish's behaviour is nearly some hours later while the water is returned as much as the splendid temp. in the event that they are feeding as commonplace then do no longer hardship approximately it. i could desire to assert, in spite of the indisputable fact that, and that i assemble you're conversing a pair of freshwater tank, that I even have on no account checked the nitrate/nitrite ranges. Ive been breeding multiple kinds of fish as a company for 10 years. your tank could desire to be set up some thing like this. an inch or 2 of commute interior the backside (for bacteria growth), some flowers, and aerator, a sturdy clear out, a mild that must be on for 8 to ten hours an afternoon, a stable heater, and that's it. in case you have all of that, then the multiple ranges of gasses and pollution will settle themselves down. as quickly as that occurs, you wont ever ought to envision nitrite/nitrate ranges. or ammonia. in basic terms pH and a speedy temp examine is all you like. while the multiple ranges blow out, it may propose that between the fish has died and is caught someplace you cant see it. have alook around and take out stuff like that. mushy crusing

The only way to lower nitrate levels is to add plants or do frequent water changes.

you need to do small frequent water changes with a gravel vac every few days until it goes down ( 15-20%) then once it does then do your weekly changes (50-75%)

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