Too Complicated?

I have a standard 75 gallon mixed reef tank with major nutrient problems. The substrate is crushed coral and the rocks have a heavy infestation of bubble algae, something that looks like an offwhite cotton-candy type algae and some hair algae.

Here is what I am thinking of doing.
1. Purchase 6 plastic storage boxes (15" x 10" x9" tall) at the local box store. These demensions would give me about the same total footprint as my current tank.

2. Purchase 120 lbs of sand and and 75 lbs of rock from Reef Rocks (site sponsor).

3. Spread out the sand and rock purchased into the storage boxes.

4. Use a small pump to pump water from my 20 gallon sump to feed the storage boxes.

4. Stacking the storage boxes on top of each other next to the tank. I would make standpipes in the upper 5 boxes that would drain down through the bottom to the next lower box, with the bottom box gravity fed back into the sump.

5. Let this system run until the sand and rock get bacteria established.

6. At this point I would drain the main tank and get as much coral off the nasty rocks and move coral and fish into temporary holding tanks.

7. Clean the DT and add the new sand and rock. When it settles down, put livestock back into tank. (Thinking maybe just a day to settle the water, so livestock is not too stressed in temporary holding tanks).

So... Am I crazy or do you think this would work.


New member
You are not crazy, that is what you will have to do. The crushed coral is feeding your nuisance algae, they only way to fix it is to get rid of it.


New member
It's easier to just house everything in totes for a day or two. Just drain your tank and move all the rock, water and fish over to totes. Get rid of the crushed coral. Clean tank really well. Clean new sand really well. Put new sand in empty tank. Pump water back Ito tank. Add rock an fish as water gets high enough. Done.

Ron Reefman

New member
Be VERY careful stacking up plastic boxes with water and rock in them. They may look stable at the time you set them up, but the flex and give over time and your entire stack could colapse.


New member
How much livestock is currently in your tank? Any chance you can buy live sand or cured live rock from a LFS? (This will cut down on any ammonia or nitrite spikes). I would recommend you transport all your livestock into the plastic boxes, no need to drill or build stand pipes, a simple air bubbler will work fine while you set the tank back up. I would then clean out the tank, diluted bleach works great for this, dispose of the crushed coral, and do not reuse. Rinse out the tank with some tap water, and add the new live sand and the new cured live rock. Start filling the tank with your old water, as long as your old water does not have high levels of nitrates or phosphates, this should be okay, if your water does have high levels of either, I would use only 25-40% of the old water and fill the rest with new RO saltwater. Once you have the tank up and running again, slowly start acclimating the livestock back into your system.
You can then start "cooking" the old live rock...get rid of the hair algae in this manner and you could then maybe either sell the live rock or trade it in for some credit at your local fish store.

Thanks for the responses. I can see where the cheap plastic totes would not support enough weight. I wanted to start with dry rock this time (cost and pest free) and get the bacteria started with my system. LFS in Corpus are lacking to say the least. Closest to getting live rock at a decent price is in San Antonio if I wanted to buy new live rock. Water shows zero on nutrients (NO2, NO3 and PO4) with my test kits, so I could resuse the water. Fish bioload is tomato clown, yellow tang, royal gramma basslet and two pajama cardinals. I have one skunk cleaner shrimp. Corals are mostly LPS, a few SPS and a couple of softies.

New question. If I go with dry sand and buy live rock, will my tank go thru a cycle? With this bioload, could the rocks be enough to filter the water until the sand becomes established? I am also using a vetex in-100 skimmer. I also have capability to run GFO, but am not using this at the moment.


New member
Look into a product called stability. I think it would help a lot since you are starting with dead rock.


New member
Mike, reusing your old water is not imperative, in fact using about 25% of it is what I would recommend, the beneficial bacteria is not free floating & you will end up just transferring more "dirty" water than anything else. If you purchase enough "cured" live rock, you should be able to avoid any spikes in ammonia & a mini cycle. Your new sand will become live again in a relatively short time.