Re-start (Nuke) reef tank?!

Heart is what matters · May 28, 2025

On a previous post i mentioned battling Dinos, raised nutrients, hired a professional reef maintenance company but the tank is looking worst and worst! Corals are dying and not happy! I Also have a big outbreak of Aiptasia

I want to nuke the tank and start over! Of course saving the fish moving them to a temporary tank!

How does one go about re-starting a tank with new rock, new sand?! And also how to i kill any aiptasia and sterilize anything left behind on tank to prevent this again? Run tank with bleach what is the process? Thank you

SOGavity · May 28, 2025

Yikes, that's too bad. I had to start over once, but only because velet killed every fish in my tank. I set up a 10 gallon tank to put the corals in, threw out the 36 gallon tank and got a 90 gallon. Filled it with new sand, let the rocks dry for two weeks (scrubbed clean with distilled water) and used reef cement to make up a new aquascape with the old rocks, bought a new sump, protein skimmer, etc, added 100% new water. I put it all back together, let it cycle for 4 weeks and slowly started the process of adding creatures all over again and now things are good. I do not regret tearing the old one down. The one I have now is absolutely gorgeous. Not saying you have to purchase a new tank, but let everything dry out, clean it, add it all in, and cycle. It's a slow process but sometimes, when you're not happy, it's worth it.

If you're going to start over, start over. Just make sure you've learned what went wrong last time and don't repeat. You're not going to want to work with something that you're not in love with and that will only result in things getting worse.

Poulpo · Jun 16, 2025

Hello, is it a recent picture? It seems not that bad that the only hope is a restart. Lots of corals seem growing. If you keep the same aquarium it will be very difficult to effectively sterilize everything. There is a risk that if you put new sand and rock some dinos survive on the equipment and use all the new space to continue with the same problems but worse. If you manage to resolve one problem at a time you will learn a lot in the process and it will be much easier to avoid them in the future. Restart is easy for small tank but complex and expensive for big tank. In big tank it is also much easier to use pest mitigation (via predator) than to keep the tank pest free forever. Can you list key info about the tank and the problems you're facing so people can help you to assess if a restart is really the best way to go?

Jimbo662 · Jun 16, 2025

I inadvertently went through something like this in Feb 2024. Due to a power issue my power heads shut off. I had very low flow through the return pump at the time. I'd been battling dinos or cyano (never figured out which) for a long time. The issue lasted for about 18 hrs before I discovered it. I'm assuming it was the lack of oxygen that killed it all off. I lost all but one fish and all but a couple of corals. The dino/cyano turned brown and the tank stunk! Tank is the frag 105.4 and I did four 17g water changes over two days and vacuumed the sand every time (this is when the odor went away). After the last water change I started dosing Microbacter 7 every day. Once the surviving corals started getting back to normal I started restocking. I got a yellow diamond goby and I've not had any issues since. Here's a video of the tank in June 2024.

Savage Henry · Jun 16, 2025

I did a restart. It was a soul-cleansing experience. Decided what rock I wanted to keep and cleaned it with bleach and then hydrochloric acid washes.

I also recycled my coral sand the same way (though the hydrochloric acid (muriatic acid) wash was brief for obvious reasons.

I had a holding tank set up for a while to keep my fish and corals while I cleaned the rock and gravel and while I allowed the rock and gravel to cycle.

Be meticulous and patient. But, you’ll still end up with some pests.

JumboShrimp · Jun 16, 2025

Go FOWLR. Enjoy life. (Lol!!)

Marco_99 · Jun 16, 2025

Unless you have totally fell out of love with your current inhabitants I don’t see it being worth it. Some elbow grease and getting everything in check look way easier and totally within reach. In the end it’s your slice of ocean and only you know what’s best for you. Most would give anything to be at this point of growth vs the time involved in starting over

ga2040 · Jun 16, 2025

It is possible to bleach and reuse the same items but requires soaking all items back in a dechlorinator like prime and air drying for few days and repeating the same steps for a few times just to be sure the bleach doesnt leach back into the system.

Idech · Jun 16, 2025

Aiptasias are in every tank and not a good reason to restart. Dinos might come back too, or something else. I’m in the same boat as you (3 years in) but I’m trying not to go the restart path in fear of regretting it.

Heart is what matters · Jun 16, 2025

Just an update everyone. I ended up re-starting the system! It kept getting worst and worst. I lost 2 of my csb anemones, torches with 20+ heads, zoas etc. surprisingly acropora was thriving. I tried to save the fish on a separate tank but some unfortunately didn’t survived. I removed all sand, rock, media balls, etc. drained the tank and filled it up with a garden hose and mixed citric acid. I let that run through the system for 24hrs. All coroline algea and gsp that was in the back came right off with a toothbrush. I then drained it and filled it up twice with clean water ran that for 48hrs. The tank has been air drying for 3 days now. I Installed a uv sterilizer hard plumbed in main display, moved the tank and re organized all the wiring.
Ordered live sand ( special grade), bacteria for the cycle, and will pick up dry rock this weekend!

A long weekend but a lot of lessons, this was my 1st tank. Now moving forward I’ll quarantine every fish before going into the main display, dip new coral properly and hopefully have more success this time along!