How to use kelp products?
 

Are products, such as Kelp Max or Alaska Pure Kelp Plant Food, to be used in addition to standard NPK fertilizers? How often are they applied, and if they are to be given in addition to fertilizer, can they be mixed or should they be applied separately? How ofter are they given? I use granular fertilizer, in a concentrated solution, and a Dosatron injector.

I followed the instructions on the bottle of my kelp mixture as to how often to add it. I usually added the seaweed when I wasn't adding my MSU fertilizer as my non-orchids had a slow-release fertilizer. It is an additive so you do still use your regular fertilizer.

It is mostly rooting hormone so yes, you still use regular fertilizer. It can be mixed with the fertilizer, which I do. I have heard it helps the roots take up the fertilizer better, but I don't know this for a fact. You should not use it all the time since they are growth hormones. I have read on some that I have usedthat you should only use it for a few weeks, then leave off for a month or so. I have also heard the plants can develop a bit of an immunity to it if used to often and since it is hormones, you could get growth anomalies if too much is used. Or just too many roots!

I was advised to use it at the rate of about 25ccs to 6.5 litres of water (my sprayer size) just once a month. As it's a seaweed based treatment it will have a wide range of trace elements, and if you are using a weak fertiliser regime, them it will just cover you in case the plants run short of any elements.

How to use kelp products?
 

In the case of KelpMax, it is to be used at 1:256 (1 tablespoon/gallon), no more often than every three weeks - I recommend monthly.

Use it at a greater dilution, and it likely won't do much. Use it at a higher concentration, or more frequently, and you may end up with deformed flowers. That's true of all hormone-containing products, and fortunately, is reversible, by merely stopping the overdosing.

I prefer to add it to the fertilizer solution, but it can be applied separately.

Like you, I have a dosing pump for the fertilizer, so I replace the watering wand with an Ortho Hose End Sprayer to add "extras".