Yes, most algae removers will indeed kill or at least stunt or really make the plants look very bad and most of them will die. They are not meant for tanks with fish either.
There are a couple of algae removers made for tanks with plants and fish but they are for green, red, and blue/green algae. Brown "algae" is not really algae, it is diatoms. Diatoms grow where there is a silicate food source or not enough light. Since your tank is new I am betting on the silicate food source. When they have eaten the silicates the diatoms will die out. The easiest and cheapest solution to the problem is a couple of Otos. BUT once you get the Otos do not even think of using a salt solution, algae remover or any medication containing Malachite Green. It will burn them as they are scaleless. It does the same thing to crustaceans (snails, shrimp, crabs, clams). You may be able to get by with salt with the crustaceans but not the other things. It will tell you right on the containers.
If your fiance is coming to go with you to buy tankmates then hope she comes and you can go get some Otos and get the Brown Diatoms eaten. They feed on them and it is their favorite food. They eat mostly at night so you will go to sleep at night and when you get up each morning, you will be surprised at their progress and before too many days have gone by the diatoms will be gone. Then you will need to put a half algae wafer in the tank at night before bed so they can nosh on it.
Rose
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