Question
The alkaline level in my outdoor fish pond is low.  I have 6 goldfish & recently I noticed one had icke.  That one has been removed from the pond for treatment.  On advise from the pet store I checked the levels & the alkaline level is low.  How do you increase the level of alkaline.

Answer
I believe you mean the pH.  An alkaline pH is one above 7 which is neutral.  A pH below 7 is acidic.  Ponds ideally should have a pH of 7.5 to 8 or so which is alkaline.  What is your pH?  If it's above 8.5, then it's too high, alkaline.  If it's below 7, then it's too low, acidic.

It's rare for goldfish in ponds to have ick.  It's more of a problem in aquariums.  Are you sure it's ick?  Male goldfish get white dots on their gill plates called tubercles.  Could that have been what you saw?

To increase the pH of the pond to be more alkaline, you need to add something that has a pH above 7, something alkaline.  For example, you could add some baking soda (sodium bicarbonate) which buffers the water to around 8 to 8.4 depending on how much you add.  How big is your pond?  You don't want to add too much at once.  They sell "pH up" which may be sodium hydroxide, a stronger base (alkaline material).  If you buy "pH up," that's a safer way to go if you're not a chemist or even if you are (like me).

Good luck!