I've been using an NPK Fertilser dissolved in water.. To be specific this exact fertilizer:

Chempak - Cactus & Succulent Fertilizer
N:P:K ~ 8:34:32 with added Magnesium (Mg) and trace elements

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I purchased this fertilizer the other day and was thinking of using this stuff to see if it gets rid of my problem:

Miracle-Gro Singles All Purpose Soluble Plant Food

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I've also got this stuff which is on the way (more plant fertilizer)

Eazifeed 250g Fast Acting Soluble ALL PURPOSE Plant Food Indoor/Outdoor

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