Father & Son IM 25 Lagoon Build

Cascadian Corals · Sep 9, 2026

Hi everyone,

New to the hobby and new to the forum. My son and I are setting up an IM NUVO Fusion Pro 2 25 Lagoon, and we're already plotting out subsequent tanks and projects for years down the road.

We're working through the shopping list slowly. So far we've got the APS stand and tank set up, and this week we started curing 10 lb of medium pukani from Tampa Bay Saltwater. Bleach soak going now, then a lanthanum chloride leach phase before it goes in the display. For anyone who's cured pukani, curious how long yours took to stop leaching?

Our TBS live sand and some base and premium nano rock land in mid-October, when the tank officially goes "live".

Attached are a few shots of the tank (with a 9gal Ikea HÅLLBAR recycling bin for an ATO reservoir) and the pukani bleach soak. The rocks are really amazing- plenty of structure to work with.

I'll post updates and pictures as we go. Looking forward to learning from everyone here.

Fish Fan · Sep 9, 2026

The 25 lagoon is a great tank!

Good luck with your build!

Tahoe61 · Sep 9, 2026

Congratulations! You will find quite a few IM 25 on R2R, my self included.

Welcome to R2R.

kevgib67 · Sep 9, 2026

What a great thing for a father and son to do together!

NeMoo · Sep 10, 2026

Agreed they’re fun little tanks!

Ethan789987 · Sep 10, 2026

The setup looks slick so far! I was looking at the 25 Lagoon a while back, but the APS stand was never in stock. Looks like they are back now, so may have to get one!

NCsalt · Sep 10, 2026

Congrats! Yall are going to have fun. My little boy has been pretty involved with our tank and loves to go to aquarium expos with me.

Cascadian Corals · Sep 10, 2026

NCsalt said:
Congrats! Yall are going to have fun. My little boy has been pretty involved with our tank and loves to go to aquarium expos with me.

My son is already asking when we can go to some expos! Also he's hoping I retire soon and we open up an LFS or coral farm together - the kid's got big plans

bristleworm · Sep 10, 2026

I'm just getting my IM 25 lagoon going myself. And my adult son talked me into it!
Just a word of caution, if you use that 9gal can for ATO reservoir when the ATO fails to shut off you will get 9gal of water on your floor.
AND coming from 50 years aquarium experience it's not if the ATO fails, it's when.

Cascadian Corals · Sep 10, 2026

bristleworm said:
I'm just getting my IM 25 lagoon going myself. And my adult son talked me into it!
Just a word of caution, if you use that 9gal can for ATO reservoir when the ATO fails to shut off you will get 9gal of water on your floor.
AND coming from 50 years aquarium experience it's not if the ATO fails, it's when.

I've been deliberating over the ATO choice in hopes of avoiding that very scenario. I'm looking at either Nature Dimensions N-Fill or a Tunze Osmolator Nano. Also, I'll have leak detection in and under the cabinet to help me respond quickly if/when things go south. Any advice on best practices to stay dry?

Delly · Sep 10, 2026

Wow !! Love the new build super cool to bring the little guy in !! I can’t wait to do this myself.

Following along !

If you have any questions post post !! We love to help. I have learned a lot in just 4 months !

Delly

bristleworm · Sep 10, 2026

Cascadian Corals said:
I've been deliberating over the ATO choice in hopes of avoiding that very scenario. I'm looking at either Nature Dimensions N-Fill or a Tunze Osmolator Nano. Also, I'll have leak detection in and under the cabinet to help me respond quickly if/when things go south. Any advice on best practices to stay dry?

It's just me but I have an ATO with float switches that has not failed me yet. My optical one has overrun the tank several times. I'm a little old school and like the mechanical float switches.

MKEnovice · Sep 12, 2026

Cascadian Corals said:
I've been deliberating over the ATO choice in hopes of avoiding that very scenario. I'm looking at either Nature Dimensions N-Fill or a Tunze Osmolator Nano. Also, I'll have leak detection in and under the cabinet to help me respond quickly if/when things go south. Any advice on best practices to stay dry?

Easiest thing would be to plug in the ATO to a smart switch and turn it on for 2 minutes twice a day. No chance for a 5 gallon spill this way.

Cascadian Corals · Sep 28, 2026

Quick update on the IM 25 Lagoon! Leak test is done, and the tank now has 28 lbs of TBS live sand and 8 lbs of mixed premium and base nano live rock (24lbs sand Treasure Chest and a TBS Pico Package).

Adding the TBS sand and rock was a blast. The whole family got involved inspecting the pieces, spotting movement, and trying to identify everything. There’s already so much to watch before adding any planned livestock!

The hitchhiker list so far includes about seven Florida cerith snails, bristle worms, Florida tube sponges, a calico clam, a feather duster worm, another unidentified bivalve, pink and white “condominium” tunicates, an orange ball sponge, micro starfish, and barnacles. We also found a tiny unidentified white crab, but unfortunately he didn’t make it.

A few water numbers after four days running:

Temperature: 77°F
Salinity: 1.026
Ammonia: ~0–0.2 ppm
Phosphate: 0.23 ppm
Nitrate: ~5–10 ppm

The Pukani is still curing separately. Its final freshwater phosphate reading was approximately 0.03 ppm after more than a week without a water change, with no noticeable smell. We transferred it to heated saltwater yesterday, and hopefully the phosphates will remain low so we can move to the display and building the final scape! Until then, the TBS hitchhiker watch is keeping everyone entertained.

Still have plenty of things to grab over the coming several weeks. For equipment, will likely grab a PopBloom 65W (temporarily using a Elgato Key Light I have for video call lighting), N-Fill ATO, and a Bubble Magus MiniQ skimmer. For livestock, looking to get a hi fin banded goby and candy stripe pistol pair, a few trochus snails, and maybe a richordea or duncan.