What's In A Box? Summertime Coral Shipping

I wanted to share some insight regarding shipping coral in summer. Maybe this will be helpful to members here who like to sell their extra frags to others, or maybe it will help customers understand the thought process in beating the summer heat for your coral. Before I created Boom Corals this year, I was a member who had shipped coral, so my experience comes from the past few years.

Recently I made the decision to buy what I'd call premium boxes, specifically from a company called Polar Tech. I think most major shippers of aquatics use Polar Tech. Even my wholesalers use them. I had been using boxes that were no name that came with 3/4" styrofoam pieces that you put together inside the box. The problem I found is that every edge had a seam and if the box didn't fit just right, as was often the case, it didn't hold temperature as well. Polar Tech on the other hand, has 1.25"-1.5" foam, and it's all one piece with a lid. I tape the lid as well to help seal the cooler.

The downside is that this increased my shipping costs quite a bit. First, the Polar Tech boxes will be larger due to the styrofoam - for example, the interior dimension (cubic inches) of a Polar Tech box that is 204 cubic inches compared to a DIY box of the same interior space, the Polar Tech box will be 1" longer in each outside dimension. So the DIY box would be say 8x8x7 but the Polar Tech for the same interior space will be 9x9x8. This increases the cost of shipping a bit. In addition, the Polar Tech boxes cost 2-3x more as well. So while a DIY box is $2-$3 per box, the Polar Tech are $5-$8 per box. So in the end, the average coral order is going to cost about $10-$15 more in shipping costs.

I decided to do a test to illustrate what would happen when the DIY foam pieces box was up against the Polar Tech. I added 2 cups of water to each bag in the tests below. Starting temp is always around 79 degrees which is in fact what I keep my aquarium water at.

I took 4 boxes total - 2 from Polar Tech and 2 from the DIY. I did two different scenarios. The first was leaving the box in the sun on an 85 F day for 4 hours, and the other was left in a hot black car that had an internal temp of 125 F for 4 hours. The bags had just the usual double/triple bagging, no cold packs.


After 4 hours, the boxes in the sun measured as follows:

-The DIY coral box water temp was at 87F which is dangerously high for coral.

-The Polar Tech coral box water temp was at 84F, which while high should be survivable for coral.

So, that's a 3F difference, enough to possibly be a life or death scenario for coral! So, there is definitely a performance difference in the boxes.

Next up is the boxes that sat in 125F heat for 4 hours. This would be a WORST case scenario, super hot early on, bright and sunny, sitting in a non AC fedex truck that is running late, etc.

-DIY box water temp was 88.7F, super dead coral territory!

-Polar Tech box water temp was 84.9F, pretty dangerous territory but the coral may survive.

Once again the Polar Tech box outperforms the DIY by about 3F, teetering on that life/death line.

For the last test, I did another extreme test scenario, the hot tarmac late in the day, hot early on non AC fedex delivery truck, etc. For this case it is another hot day, about 80F ambient temp, sunny, and the inside of my black car is around 115F. I set up two polar tech boxes, one with just the bag of water triple bagged, and the other the same but with an "ice brix" cool pack. The boxes sat in the car for 3 hours like this.

-Box without cool pack water temp was 82.7F, not ideal but still survivable for coral.

-Box with cool pack water temp was 76.6F, which is much better.

We'd rather have the temps go down than up, as coral can survive cooler temps far more easily, even getting into the low 70s and maybe even high 60s without an issue.

In the end, there's something else I want to point out that a lot of people don't think of. Sometimes when a customer receives their order and all the coral are alive they'll say to me "It's 90 degrees out why didn't you use a cool pack?" The reason is that while the high for that day may be 90, it might not reach that until 2pm or 3pm in the afternoon. But the temp when I shipped it at 5pm the evening before was 70, and the temp in the hub overnight was 65, and the temp before 11am at the destination was in the 70s (fedex priority delivery is by 10:30am in most places). So that's what I need to pay attention to the most, not the high of the day, but the temps from shipment to delivery. A cool pack can do damage if used when it shouldn't be. I did do a test with a cool pack on an evening where the temps were around 67F and after sitting overnight, the water in the bag was 62F. That's quite cold!

In the end, I do my best to determine when to use a cool pack in summer and when not to, and most times I'll get it right. For my customers my DOA policy goes well beyond the day of delivery, so you're covered either way. I hope you found this article interesting and informative!
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