If your little one’s first birthday has an “Oh Fishally One” theme, you already have great taste.
The pun is adorable. The color palette of ocean blues, teals, coral, and gold is genuinely beautiful. And the decor options are so much fun to pull together. All the underwater details come together into something that looks genuinely polished and playful at the same time.
Here are the 9 decorations you actually need to make the setup look complete.
1. “Oh Fishally One” Banner
This is the anchor piece for the whole party. Everything else on the dessert table or backdrop will orbit around it.
Etsy has dozens of sellers who do beautiful versions in ocean blues, gold, and teal. Some come as letter balloons, some as printed fabric banners, and some as a mix of both. Whichever format you choose, make sure it is large enough to read clearly in photos from a few feet back.
If budget is tight, printable versions are widely available and look great when printed on cardstock and strung on a simple twine line.
2. Balloon Garland in Ocean Colors
Out of everything on this list, the balloon garland makes the biggest visual impact. This theme gives you a gorgeous palette to work with.
Mix navy, teal, aqua, and white balloons in different sizes and weave in some gold balloons for warmth. Organic style garlands look far more beautiful than the symmetrical kind. The balloons cluster together naturally rather than sitting in perfect rows and the result feels intentional rather than manufactured.
Add some blue and teal streamers or strips of sheer fabric into the garland to give it movement and texture. If you want to go the extra mile, tuck a few fish or starfish foil balloons into the arrangement.
3. Fish and Sea Creature Balloons
Beyond the main garland, individual character balloons add so much personality to the setup.
Goldfish shaped balloons, clownfish balloons, octopus balloons, and starfish foil balloons are all widely available on Amazon and party supply sites. Float a cluster of them near the dessert table, tie a few to the back of the birthday baby’s high chair, and scatter a couple around the party space.
Character balloons photograph really well and make the whole room feel fully committed to the theme rather than just having a banner and some blue balloons.
4. Under the Sea Backdrop
Every photo at this party gets taken in front of the backdrop, so it is worth putting real thought into this one.
A few directions depending on your budget and how hands-on you want to get. A balloon garland backdrop mounted on a simple pipe and drape frame is the most popular choice and looks stunning. Large paper fans in graduating shades of blue and teal create a beautiful ombre ocean effect. Sheer blue fabric with fairy lights woven through it photographs like actual light filtering through water.
Whichever direction you go, add some paper or foil fish, starfish, and seaweed cutouts to the backdrop itself to make it feel fully dressed.
5. Bubble Details
Bubbles are massively underrated for an underwater theme and almost free to execute.
Clear round balloons of different sizes scattered across the ceiling, hung at different heights above the dessert table, or clustered in a corner immediately read as giant bubbles. Tie them with clear string so they appear to float on their own.
Mix in some iridescent or pearl finish balloons to add a subtle shimmer effect. The result looks like the whole party is happening inside an actual underwater scene and it always gets a reaction from guests.
6. Seaweed and Coral Garlands
Green paper garlands twisted and hung to look like seaweed, paired with coral colored paper or fabric pieces, bring the underwater environment to life in a way that flat decor cannot.
Hang seaweed garlands from the ceiling above the dessert table, drape them across the backdrop, or let them fall from the edge of the table to the floor. Pair with small coral colored balloon clusters or coral shaped paper cutouts positioned around the base of the table.
This detail is something a lot of people skip and it is exactly the kind of thing that makes a party setup look genuinely thought through.
7. Treasure Chest and Pearl Details
Place a small decorative treasure chest on the dessert table and fill it with gold coins, pearl beads, or candy in gold wrappers. It connects to the underwater theme without being heavy-handed and adds a really charming story element to the setup. Position it near the base of the cake stand or at the end of the dessert table. Scatter a few loose pearl beads or gold coin decorations around it. Add a small “One Year of Treasure” tag if you want to tie it back to the birthday.
Kids love spotting it and adults always comment on the detail.
8. Personalized Cake Topper
Birthday cakes look generic without the right topper. This is what makes it feel personal to the theme.
For an “Oh Fishally One” theme, look for a custom acrylic topper with the phrase on it, or a wooden cutout in the shape of a fish or wave with “One” written through it. Gold or teal acrylic toppers catch the light beautifully in photos.
Pair the topper with a cake in ocean blues and teals with scale or wave textured buttercream, and finish with a few fondant fish or pearl details around the base.
9. High Chair Decoration
Baby’s high chair gets photographed constantly at a first birthday, especially during the cake smash. Give it the same attention as the rest of the setup.
Hang a sheer teal or blue fabric canopy above the chair and it instantly becomes a little ocean throne. Add a small “Oh Fishally One” banner tied across the front of the tray or draped over the chair back. Tuck a few small fish balloons or a starfish balloon arrangement on one side.
Finish with a simple flower or sea creature headband for baby and the whole setup becomes a photo moment that looks completely intentional.
Wrapping Up
You do not need every single decoration on this list to make the party look incredible. Pick the ones that excite you most, execute them well, and let the theme carry the rest.
The banner, balloon garland, and backdrop do most of the heavy lifting. Add the bubble details and the high chair setup and you are honestly already there.