Black Mollies for Live-Rock-Culture Tank

[Soren]

With a recent order from Gulf Live Rock, I started a 90-gallon tank with a 44g Brute sump for isolating ocean-direct live rock and culturing dry rock from the live rock.
Algae is starting to grow all over this tank, and I am looking for methods to keep it in check.
The issue with remedy consideration is that I want to keep some of the types of algae for culturing in refugiums/macroalgae tanks (such as halimeda), so I don't want these to get eaten. I also don't want the coralline algae to be consumed, since it is one of the primary reasons I wanted to order and culture live rock.
The live rock included several small corals and a couple gorgonians that I would also like to keep, so I don't want to add something that will harm these corals while trying to remedy algae issues.

What are your thoughts/opinions on adding black mollies to this tank for algae control and a bit of fish movement for interest-sake? Are there other small, relatively cheap fish recommended instead? Should I just get snails and/or small hermit crabs for this tank?
I do plan to stock a few fish in this tank during long-term live-rock culturing, so I'm open to suggestions for what to consider. The primary purpose for this system is to allow natural small life forms (bacteria, pods, worms, etc.) to thrive so I can determine what I want to use to seed these life forms into other tanks.

I currently have black mollies breeding (excessively) in a freshwater 40g tank, so I have easy access to stock for the live-rock-culture tank if I go this route.

I'm open to any suggestions that fit my plan of a long-term live-rock-culture tank.

 

[Shooter6]

Mollies will help, and also help with feeding via poop the good stuff on the rock.

Personally I'd set up a bucket algae scrubber or cheato reactor.

I'm assuming the tank has an overflow and drains into the brute? If so then put the bucket reactor in line between the two.
Or if that's not an option see if you can put a shelf above the tank and either the bucket or another container to grow algae in above it. Have the return from the tote feed into it then drain back to the tank.

I have a 300g fiberglass tote sump. I have a couple of the black pool skimmer baskets floating in it that I grow hair algae in this keeps my phosphate and nitrate near undetectable ranges. I actually over feed and dose both as needed

 

[Soren]

Mollies will help, and also help with feeding via poop the good stuff on the rock.

Personally I'd set up a bucket algae scrubber or cheato reactor.

I'm assuming the tank has an overflow and drains into the brute? If so then put the bucket reactor in line between the two.
Or if that's not an option see if you can put a shelf above the tank and either the bucket or another container to grow algae in above it. Have the return from the tote feed into it then drain back to the tank.

I have a 300g fiberglass tote sump. I have a couple of the black pool skimmer baskets floating in it that I grow hair algae in this keeps my phosphate and nitrate near undetectable ranges. I actually over feed and dose both as needed

Tank is drilled with two bulkhead overflows into Brute. I like the idea of algae scrubbers in the sump/drains, as this is similar to what I am considering for my main 125-125 build. Skimmer baskets are a great suggestion!

Mollies may still get added to the main tank along with adding algae scrubber to sump can.
...as long as they don't reproduce like crazy in the saltwater tank like they do in my freshwater tank. That could get to be quite a pain in a tank this size...

I definitely want to add fish/inverts to this tank to complete the ecosystem, but I don't want to add anything that shifts the focus away from the primary purpose of culturing live rock.

 

[NowGlazeIT]

Have you gone through the initial break in period for this tank? You know the ugly phase. I think the algae is just burn off from any die off (from the rock shipment) and or surfaces needing that sweet reef biofilm

 

[Soren]

Have you gone through the initial break in period for this tank? You know the ugly phase. I think the algae is just burn off from any die off (from the rock shipment) and or surfaces needing that sweet reef biofilm

The rock has been in the tank now for about 3 weeks. Does ocean-direct rock go through an ugly phase that should just pass with time?
Maybe I just need more understanding of live rock.
I've been feeding this system with only live rock, and I expect algae to continue to grow unless I get something that eats it since I have no other export of nutrients. This might be solved if I add algae scrubbers as suggested above and remove excess nutrients here.

Should I just wait in the hopes that desired algae will beat out the hair algae for nutrient competition? The hair algae is spreading quite rapidly and even covering some other organisms on the rocks, such as clams and sponges. There is also a bit of cyanobacteria starting in a few locations. Is there any way to improve stability and get past the ugly phase other than just waiting it out?

 

[NowGlazeIT]

The rock has been in the tank now for about 3 weeks. Does ocean-direct rock go through an ugly phase that should just pass with time?
Maybe I just need more understanding of live rock.
I've been feeding this system with only live rock, and I expect algae to continue to grow unless I get something that eats it since I have no other export of nutrients. This might be solved if I add algae scrubbers as suggested above and remove excess nutrients here.

Should I just wait in the hopes that desired algae will beat out the hair algae for nutrient competition? The hair algae is spreading quite rapidly and even covering some other organisms on the rocks, such as clams and sponges. There is also a bit of cyanobacteria starting in a few locations. Is there any way to improve stability and get past the ugly phase other than just waiting it out?

If you have live rock then it won’t be long till you’ve reached stability, I would say your right around that time where things will start to settle out. Keep removing the unwanted algae and add a few inverts to help you there. If your low on filtration gear then keep up with water changes and you’ll see the nuisance algae start to burn off.

 

[Soren]

If you have live rock then it won’t be long till you’ve reached stability, I would say your right around that time where things will start to settle out. Keep removing the unwanted algae and add a few inverts to help you there. If your low on filtration gear then keep up with water changes and you’ll see the nuisance algae start to burn off.

I'll give this a try a while longer before adding black mollies, since I really don't want the mollies to breed like crazy and overpopulate the rock tank.

 

[Shooter6]

Tank is drilled with two bulkhead overflows into Brute. I like the idea of algae scrubbers in the sump/drains, as this is similar to what I am considering for my main 125-125 build. Skimmer baskets are a great suggestion!

Mollies may still get added to the main tank along with adding algae scrubber to sump can.
...as long as they don't reproduce like crazy in the saltwater tank like they do in my freshwater tank. That could get to be quite a pain in a tank this size...

I definitely want to add fish/inverts to this tank to complete the ecosystem, but I don't want to add anything that shifts the focus away from the primary purpose of culturing live rock.

I've got some in my 400g. They reproduce about as fast, but the babies always end up in my sump. Unfortunately they are stupid so most end up disappearing via skimmer pump, return pump, or basket with Colorado sunburst nems.

 

[Duncan62]

Tank is drilled with two bulkhead overflows into Brute. I like the idea of algae scrubbers in the sump/drains, as this is similar to what I am considering for my main 125-125 build. Skimmer baskets are a great suggestion!

Mollies may still get added to the main tank along with adding algae scrubber to sump can.
...as long as they don't reproduce like crazy in the saltwater tank like they do in my freshwater tank. That could get to be quite a pain in a tank this size...

I definitely want to add fish/inverts to this tank to complete the ecosystem, but I don't want to add anything that shifts the focus away from the primary purpose of culturing live rock.

They will reproduce but the survival rste in saltwater seems to be less. I think mollies are a good idea.

 

[SteveMM62Reef]

Small Foxface, move it to the 90 gallon, and rehome it when it gets too big. They are voracious green algae eaters, and won’t touch anything else. Also they usually aren’t aggressive, but will hold their own against aggression.

 

[Soren]

I've got some in my 400g. They reproduce about as fast, but the babies always end up in my sump. Unfortunately they are stupid so most end up disappearing via skimmer pump, return pump, or basket with Colorado sunburst nems.

They will reproduce but the survival rste in saltwater seems to be less. I think mollies are a good idea.

Thanks for this information. I'm still considering adding some mollies to see how it goes. If they do reproduce excessively, I might have to start making my own cat food or something.

Small Foxface, move it to the 90 gallon, and rehome it when it gets too big. They are voracious green algae eaters, and won’t touch anything else. Also they usually aren’t aggressive, but will hold their own against aggression.

Foxfaces are already in my considerations since they are my favorite fish and I already have some including 2 that are about 3" long that I am seriously considering housing in the 90g rock-culture tank for a while. The concern I have with them is that part of the reason I wanted ocean live rock was to obtain interesting algae to grow for foxface food. I want the hair algae kept at bay but do not want the other algae types to be consumed before I know what they are and if I want them for culturing.

Thanks for suggestions and advice!

 

[Shooter6]

Small Foxface, move it to the 90 gallon, and rehome it when it gets too big. They are voracious green algae eaters, and won’t touch anything else. Also they usually aren’t aggressive, but will hold their own against aggression.

Foxface sometimes do eat coral. And fish for that matter. I've got a big one in my 300g sump for this reason.

 

[Shooter6]

Thanks for this information. I'm still considering adding some mollies to see how it goes. If they do reproduce excessively, I might have to start making my own cat food or something.


Foxfaces are already in my considerations since they are my favorite fish and I already have some including 2 that are about 3" long that I am seriously considering housing in the 90g rock-culture tank for a while. The concern I have with them is that part of the reason I wanted ocean live rock was to obtain interesting algae to grow for foxface food. I want the hair algae kept at bay but do not want the other algae types to be consumed before I know what they are and if I want them for culturing.

Thanks for suggestions and advice!

Honestly I doubt the reproduction would ever become an issue. If your system is ich and velvet free, and you use black mollies, those babies can be sold . People will use them for qt systems ect as tester fish.

 

[Soren]

Honestly I doubt the reproduction would ever become an issue. If your system is ich and velvet free, and you use black mollies, those babies can be sold . People will use them for qt systems ect as tester fish.

I'll have to look into the market for baby black mollies. Currently, my 40g breeder freshwater tank is only population limited by space/resources, I'm pretty sure. They are so cheap at the chain pet stores that I don't think I'll find much market for them in my area...

 

[BurtG]

Weirdly I actually had trouble finding any healthy black mollies in my local area last month. Every store had them, but they were no where near healthy. I did eventually find a few after hitting up a half dozen stores.

 

[Shooter6]

Weirdly I actually had trouble finding any healthy black mollies in my local area last month. Every store had them, but they were no where near healthy. I did eventually find a few after hitting up a half dozen stores.

Same here and the freshwater ones are hit and miss transitioning to salt.

I dont know about you all but the market price for fw black mollies is about 10.00 each around here. So sw ones should fetch at least that much.

I've got 1-2 blacks left a couple of the Dalmatians and an orange sword in my 400g currently.

Thinking about it, ill probably pick up a couple dozen more this weekend!

 

[Lost in the Sauce]

IMHO, a single lawnmower Blenny works so what you're wanting. 4 black mollies ( direct dump in) couldn't keep up with the algae on 60lb of KP rock for long in isolation

 

[Soren]

Weirdly I actually had trouble finding any healthy black mollies in my local area last month. Every store had them, but they were no where near healthy. I did eventually find a few after hitting up a half dozen stores.

Same here and the freshwater ones are hit and miss transitioning to salt.

I dont know about you all but the market price for fw black mollies is about 10.00 each around here. So sw ones should fetch at least that much.

I've got 1-2 blacks left a couple of the Dalmatians and an orange sword in my 400g currently.

Thinking about it, ill probably pick up a couple dozen more this weekend!

I guess I'll have to check it out. FW black mollies are about $2-3 in my area and are always available, typically healthy (though ich is not uncommon from the chain stores but much easier to deal with in FW).

Mine are already established, healthy, and breeding in my 40g FW tank, so they are easily available and super cheap for me.

 

[Soren]

IMHO, a single lawnmower Blenny works so what you're wanting. 4 black mollies ( direct dump in) couldn't keep up with the algae on 60lb of KP rock for long in isolation

I was hoping you'd catch this thread and give some advice. I'll be checking into a lawnmower blenny right away!
Do you recommend only one lawnmower blenny for a 90g with 75lbs GLR rock?
Also, do you know if lawnmower blennies typically eat nuisance algae like green hair while leaving other macroalgae alone, or are all types at risk of consumption?

I'm still considering being unconcerned with what algae types I lose and just buying specific types in the future for addition, although I do like some of the types growing on the live rock right now. (I need to find time for more pictures for sharing and for my own records...)

 

[Lost in the Sauce]

I have a 6" lawnmower in my frag tank. It has Removed all of the fine whispy filament types of algae from KP live rock including gha and rha. Left the Gorgs, halimedia and some broader leaf algae completely alone. They don't just pluck, their mouth actually scrapes the surface of the rock removing the algae from where it was growing. They can't get to the base in deep holes, but will do some a serious Work.

I cannot recommend two to a tank. I tried to qt two in the 40b at the same time. One killed the other So quickly I didn't even have an opportunity to respond. I may have had two males. There's a chance a male and a female would do fine together. I do not know so cannot recommend it.

Mike over at Dr. Reese quarantine fish. Pretty much always has them in stock, healthy And ready to ship.