What do you mean by drainage? Hopefully you mean drainage holes in the pot and not pebbles or something similar in the bottom.

the pot looks too large for the plant, especially coupled with the heavy peat soil which is very water retentive.

How often do you water? And how much water do you give it?

how far from the window? It should be as close as you can get it.

Spider plants are very sensitive to chemicals in tap water. That's likely the cause for the brown tips.

Your issue are probably overwatering, lack of light and chlorine and fluoride in the water.

Yes, it has drainage holes. I water whenever the soil is dry and I water until it drains from the bottom. It is not very close to the window. I will repot into smaller pot and put it closer to the window..Thanks for the tips.

Get a wooden dowel and sharpen the ends. Stick it in the soil all the way to the bottom.

Pull it out right away and inspect. If it comes out dark, damp and stained with soil, do not water. Wait until it comes out clean and dry. Then throughly water until it comes out the drain holes. Always discard water collected in the saucer right away.

I really like the all green spider plants!

I have had Spider plants bounce back after looking terrible. Mine really took off after bringing it outside in the summer. I also put it in a fast draining mix. Not quite the 5-1-1 that is popular here. I probably mix equal potting mix, perlite and pine fines partly because bark is hard to find, and partly because once I bought my plants inside watering became a chore with5-1-1 especially with my hard to reach plants. (You can search 5-1-1 mix here for more info).

I would let it dry out before watering. Some people use a chopstick or bamboo skewer to test how wet the mix is near the bottom of the pot. Around Father's Day repot it into a faster draining soil, and I have pretty aggressively pruned the roots on spider plants if needed too. When the weather is consistently above 55 degrees bring it out into a shady area. Last year I had one ina shady area I slowly acclimated to full sun and it took off like gangbusters.

Lastly, like it was mentioned tap water may have too much fluoride and chlorine. Leaving water on the counter will help with chlorine but not flouride. I don't water exclusively with rain water or distilled water like some folks but I do use both occasionally, when I think about it. Spider plants do seem more sensitive to flouride.

Good luck!