Can't you go to Home Depot to get some pumps there?

Which one to pick... Well, depends on how/what you want to do with your 4 plants.

Air Stone: It's a "stone" with many, many, many pores (Garden Knowm was counting them one day, and he hasn't finished yet). Anyways, these pores throw millions of tiny air bubbles into your nutrient mix.

You know fish aquariums? The air bubbles rising? That's made by an air stone. Or "air rope"... but that's basically an uber-airstone.

You need an air pump for your air stone... get the best air stones and air pump your budget can allow.

If you go DWC with your four plants, in 5 gallon buckets, you can skip on the water pump... unless you want a recirculating system... Anyways, yes, you really really do need a GOOD dual-outlet air pump, and GOOD air stones.

Best,

-turtle420
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