Converting a Marine tank to Freshwater

[Fisher_Zeb]

Hi all, I recently got my hands on (for free) i think its a 120 gallon tank with a 30 gallon sump and need to know if anyone by experience has had to do anything specific to clean it out or prep it for Freshwater.


Aqua medic 120

I.E do the pipes on the overflow need cleaning, would there be any remaining salt left anywhere which would effect water chemistry etc.
Thank you

[Hardy85]

I'd think all you need to do is run some fresh water through it and give it a good wipe down, just like any used tank.

If your nervous about it, just do a fishless cycle and you won't be risking anything :), maybe do a few water changes just encase. But i don't think a little salt would hurt anyone. Unless you had very delicate fish..

[Cliff]

If the tank has coraline algae on it, then you will need to clean it off with vinigar and possibley scrap it a little to. A good rinse won't take that off the glass. You do not want a lot of dead coraline algae still in the tank if you are going to use it for freshwater.

In addition, do your best to remove all the salt, but also keep in mind that trace amounts of salt won't hurt anything

[Fisher_Zeb]

Ive looked up that Cliff but i dont know what i looks like "dead"
it does have alot of white hard stuff in some places esp the sump, is that it do you think?
I will try get some pics tonight



- think it is that though, pretty certain. Its all over the overflow really and inside it.
I dont have a clue how to get some parts off to be honest as theres places where it is where hands cant simply get.

Does the littlest amount of this stuff cause harm?

[Cliff]

Yes, the hard white stuff is dead coraline algae. If there is enough of it, it can effect the amount of dissolved minerals in your water, a lot like crushed coral can. It may or may not be a significant risk, but why take the chance.

[4Charlie]

I got a 180gal reef tank from one of my daughters and I set it up in fresh water. The white hard stuff got to be a pain so I just left it on there. So far no side effects to the fish in the tank. Good luck...

[CrazedMichael]

If Cliff said to me that dead coraline can affect water params if there is enough of it, i'd be trying my best to scrub it all off. After all, he knows more about saltwater fishkeeping than most of us here so i'd listen to him.

In the pic it looks like it should be easy enough to disassamble most of the parts so why not do that and then give it the bees with elbow grease. For pipes and stuf maybe a long soak in water with vinegar followed by a good scrubbing with a bottle brush or something similar.

In regards to salt, i wouldn't worry too much about it if the tank has been well cleaned. After all, most of us has come across Ich at some point and have treated with Salt and heat. As long as you don't have salt sensitive fish such as invertebrates in the tank, you should be fine. After a few months of regular WC's, the salt should not be present anymore.

[Cliff]

When I took down my 90 gallon reef tank, I cleaned everything out of the tank and sump by wiping it down with fresh tap water. I then filled it with tap water and about 1 to 2 gallons of vinegar and I ran the set-up for about 3 or 4 days. After doing that, about 75% of the coraline just wiped away with little effort. The rest I had to scrape a little with a one of those plastic scraping edges. You might want to give that a try first as it may help

[Fisher_Zeb]

Okay well thank you for all your help, ive got some pictures below.
Im a little affraid to mess with the pipes never mind take them out!This is my first experience with a overflow,
I apparently need to silicone the pipes under the tank to stop it leaking as the previous owner removed the silocone to attempt to take the pipes off but never in the end.

The tank wouldnt be set up for so time with this tank isnt a problem.

If you could just rotate your heads to the right (sorry, silly phone)
If anyone wants to know anything which is what i can label and rotate to right angle etc.



Outlet


Inlet


Inside overflow

[Fisher_Zeb]

Inlet pipe going to sump


The Tank