Hey @hcarter2228, that's a good question about placing Formic Pro on top of a two-deep hive instead of between the brood boxes. What's making you consider that particular placement? Sharing a little more about your setup might help folks who have tried it weigh in with their experience

 

Who invited the robot into the conversation?

 

that happened because nobody replied to the original post.

we can keep ff from chiming in if a human replies within a day or so from the op.

 

so next time I'll just post "f..." instead of hitting the follow button to keep FF from joining with a non-answer.

 

yes. i missed this one, but usually i will reply to a new member with a welcoming post.

@hcarter2228, welcome to beesource.

what ruth and i are talking about is the first reply to your question was posted by a robot that doesn't know beekeeping.

i don't have experience with formic pro, but hopefully someone will chime in with an answer to your question.

 

It'd be safe. There are dispensers for liquid formic that have to be ontop in a shim anyways.

Formic pro is designed to be close to the brood. If the brood nest is entirely in the upper deep, you're probably better off putting the pads on top imo. If split or entirely in the lower, put above the lower deep.

I don't get good knock down with formic when it has to go through a box of honey.

 

This year, I placed two pads on top of the two deeps (honey super, two Formic Pro pads, deep, deep, bottom board with the entrance fully open). In 2020, I followed the recommended placement (honey super, pad #1, deep, pad #2, deep, bottom board with the entrance fully open). In neither case did I see many dead bees around the entrance. However, in terms of effectiveness, the recommended method performed better.

The following tables show actual mite drop counts during 24 hours, unless otherwise noted. Pre-treatment natural mite drops were similar in both years. However, the total number of mites dropped during the two-week period was at least 3,506 with the recommended method, compared to 1,288 with the two-pads-on-two-deeps method. Post-treatment natural mite drops were also lower with the recommended method.

2020 Data (recommended method)

Date	Days after treatment	24 hr mite drop (unless noted)	Note
8/17/2020	-3	23
8/18/2020	-2	25
8/19/2020	-1	30
8/20/2020	0	32	Formic Pro: one pad on the deeps, one between deeps
8/21/2020	1	48	12 hr count
8/22/2020	2	673
8/23/2020	3	365
8/24/2020	4	324
8/25/2020	5	379
8/26/2020	6	361
8/27/2020	7	332
8/28/2020	8	313
8/29/2020	9	280
8/31/2020	11	340	48 hr count
9/2/2020	13	not done	Mite board cleaned but not counted
9/3/2020	14	91
9/6/2020	17	61	72 hr count, pads removed
9/7/2020	18	41
9/8/2020	19	6
9/9/2020	20	9
9/10/2020	21	8
9/11/2020	22	8
9/12/2020	23	7

2025 data (two-pads-on-two-deeps)

Date	Days after treatment	24 hr mite drop (unless noted)	Note
8/26/2025	-3	29
8/27/2025	-2	30
8/28/2025	-1	30
8/29/2025	0	45	Formic Pro on the two deeps, at 6:00 PM
8/30/2025	1	99	12 hr count
8/31/2025	2	178
9/1/2025	3	128
9/2/2025	4	81
9/3/2025	5	85
9/4/2025	6	88
9/5/2025	7	100
9/6/2025	8	70
9/7/2025	9	84
9/8/2025	10	79
9/9/2025	11	88
9/10/2025	12	88
9/11/2025	13	85
9/12/2025	14	35
9/14/2025	16	42	48 hr count, pads removed
9/15/2025	17	15
9/17/2025	19	19
9/18/2025	20	11

 

This mite count thing is a little too anal for me. Once I get above 20 count, I start counting by tens, do it quickly, and the ones digit is occupied by a zero! In fact, I don't even count mites.
And I remain too chicken to use the formic pro again.

 

Using formic has never been a problem for me, probably because summers in the Pacific Northwest are relatively cool and very dry. Yes, counting mites is a hassle, so I may only tally 1/3 or 1/4 of the board, or just take photos and review them later if something seems off. The two examples I shared are rare cases where I did an almost complete count throughout the Formic Pro treatment.

 

Search Randy Oliver's Scientific Beekeeping site about using formic pro.

He's in California and simply covers the top of formic pad with the foil packet it came in. This limits off gassing to one side of pad. It evens out and extends the off gassing. Virtually eliminates that massive discharge on hot days when first installed and results in no queen loss.

 

Hey, I think the robot did OK at asking for more details! It is well worth asking "what's the problem/fear/issue behind this departure from the standard practices?

The instructions don't say to do anything but place the pad(s) between the brood boxes, so the idea is to keep the pads IN the brood area, where they are subjected to the fairly constant temperature and minimum humidity of the brood chamber, conditions which the bees strive mightily to maintain. If you have brood filling two boxes (for example, I run nothing but mediums - I own no deeps) then you have to use some judgment on placement to get them IN the brood area.

Here's the instructions, with handy illustrations: Formic Pro Application - NOD Apiary Products Ltd.

Search Randy Oliver's Scientific Beekeeping site about using formic pro.

He's in California and simply covers the top of formic pad with the foil packet it came in.

That's going to limit the outgassing, and limit the treatment. Again, this does not follow the label instructions, so it is suspect, and is not likely to be an effective control, or the vendor would have made the pads with one side being foil or otherwise impermeable.

 

Don't forget that Randy Oliver advocated for off label placement of Apiguard several years ago that had disastrous results.
To his credit, he later recanted that advice.

 

Can we all agree that formic pro is not a great product? It is under the required dose to kill mites under cap. The advantage of formic acid is it CAN kill over 90% of mites under cappings but Formic Pro does not.

So, if you are going to use this product for an entire cycle of bees under cap then you do not want that large off gassing when first introduced to the hive. If you do want that then I suggest going off label and using formic acid in a flash treatment. If you are wanting to kill the mites as they emerge from cap then you want the product to be stable for the duration to do so. Full pad exposure is heavy off gassing for first few days then less and less gassing over the 12 day period of mites under cap opposed to a steady release that kills the mites the full duration. You should read Randy's study of this "off label" application with foil on one side and make your own determination.

 

Can we all agree that formic pro is not a great product?

No