Tank Rehab, need Advice!

Hello! I have become the general caretaker of a 75 gallon reef tank that has fallen on some hard times. This tank was mine for a decade or more in the early 2000s and when I moved out, my parents asked to keep it and my wife asked me to leave it. Over the last 5 years or so they managed pretty well, we had great success with LPS, SPS, a number of fish. Its got some great quality equipment too, nice lighting, lively and healthy sump with cheato and some hermit crabs. A nice g1x protein skimmer that apparently just kicked the bucket again (the pump died I believe) and lastly a nice healthy selection of live rock.

I know that my parents have not done water changes like they are supposed to and this has resulted in some major coral losses. We lost all of the SPS and almost all of the LPS. Salt spiked because of a failure in the auto topoff from a RODI, chemicals are unbalanced and I know that there is a lurking monster in the sandbed which is no longer evenly spread. Lastly, some softies have kind of taken over, mostly a particularly prolific breed of Green Star Polyps and Blue Star Polyps. I am looking for some advice to get this guy revitalized and ready to accept LPS and SPS corals again, as I take over the care of it.

I want to take the next few months to make sure it is in working order and so I guess my major question is… what is your advice for me getting this guy back in order? I will get test numbers here later today, I plan on going over there. And I am looking to reduce the GSPs in there significantly, so if there is anyone who wants to rehome this big rock (10" long, 4" wide) full of GSPs, I would be interested in setting something up.

Welcome to the forum @sweeneycam!

We’ve all been where you are in one form or another :slight_smile:

There are two approaches, in my mind:

  1. Start back up with regular maintenance and pull out the rocks with the invasive corals on them.
  2. Reboot the tank from scratch.

It sounds like you’re in a better spot for #1, but sometimes a full reboot can do wonders. I did one about 18 months ago and I’m extremely happy I did.

I’m sure a local store, like Frags 2 Fishes, would be willing to take the large rocks with coral on them from you for store credits.

@Donavon is in the midst of a reboot right now too, actually. What do you think?

Welcome to the club

  1. Replace all the cartridges in your RO/Di unit including the membrane.
  2. Remove all dead corals from the tank
  3. Get the protein skimmer back up running
  4. Make up new RO water for a 20% water change @15 gallons
  5. Mix in salt to RO water and let sit overnight with a heater to proper temp
  6. Do 15 gal water change, next day check parameters.
  7. Do a 2nd water change 1 week later check parameters next day
    This is just my opinion to get the tank slowly back. I am sure other members will contribute to the process.
    Good luck, take your time

I decided to completely reboot my tank but there was good reason for it. I had some invasive aiptasia anemones, algae issues, and wanted to do away with the deep sand bed.

If you are not have ong major algae issues then my guess is corals probably perished due to alkalinity, magnesium, and calcium deficiencies. It’s hard to say but my guess would be if it was excess nutrient issues you would be battling Algae.

I would say follow along the lines of what Houndsbayman is saying above.

Get the tank generally cleaned up, get rid of unwanted/nuisance coral, get a husbandry routine in place and once parameters are stable/consistent start introducing desirable coral a few at a time every couple weeks or so.

Go slow with getting the coral back in and monitor their needs/usage of elements regularly.

I am about a week or two away from starting to introduce corals myself and am planning to do a few each weekend so I can monitor the changing needs


I would look for ways to automate away as many processes as possible. Some thought to consider below:

  1. Top off - I use a Tunze osmolator.
  2. Dosing - I use a cheap Jebo pump - Baking soda for Alk and Kalk for Ca/Alk/Ph boost
  3. Feeding - $20 amazon rechargable feeder w/ PE pellets
  4. Export - I use a skimmer, but I also prolifically grow chaeto algae which is a big part my nutrient export. I also run on an opposite light schedule to help with Ph swing
  5. Mixing station - If you have the room to work with set up a dedicated space to hold fresh and mixed sea water. Always good to have atleast a few gallons in reserve.
  6. Testing - Hanna Alk checker is super easy. The ultra low PO4 is a bit more challenging. I use salifert for everything else.
  7. DC pumps - I love the idea of DC pumps. much less energy consumption and flow is easily controllable - I use cheapo Jebos - Thinking ill upgrade as time goes on
  8. Flow - important for nutrient export. Love my MP40, but expensive. I also use Jebo gyre style pumps and those work pretty well, also cheap.
  9. Rock structure - While it is significantly more work, my rock is drilled and held together with 1/4 in fiberglass rods. I easily disassemble my rock scape. My frags sit on custom tiles with pegs to make moving colonies super easy. biggest downside is upfront TIME commitment.

there’s always more. good luck