Trying to Understand SaltWater

[ReefNewb82]

Hello everyone!
I joined the forum because I recently started volunteering at a household that houses the elderly (slightly different than an old folks home lol)
They have a large tank, 1 person said it was a 200 Gallon. Unfortunately I do not have any experience with Saltwater, the largest tank I own is a 120 Gallon Freshwater tank. The man that was in charge of the tank passed and the rest are just feeding and refilling the water haha.
I will post a few pictures tomorrow hopefully, but it has definitely seen better days. There is a lot of green on the glass, I am assuming algae.

Long story short, we sold a bunch of stuff in the house and have about $300 to try to fix the tank up.
Based on some of my research for saltwater tanks I had some questions that I can't understand.

1) They have a 75 Gallon sump, skimmer is no longer working, is it necessary to have a protein skimmer? OR is it better to do a refugium. They do have a lot of rock and sand, and based on what I read online, all I would have to do is just put some of the rock in the sump and buy some Chaeto and an LED light and that would help with the filtration, which would be better?
Is the sump big enough? For a large tank which is the preferred method?

2) Is 10% water change every 2 weeks good enough? Not including top offs.

3) This question is more for myself, not planning on doing anything with this tank except keep the fish alive and the tank looking clean but do you guys use like some sort of liquid fertilizer for all your amazing corals? In freshwater I use Thrive for the plants, how do you guys grow your amazing corals, can you pull it off just using proper light ( question for the future if I ever go saltwater).

Thanks for the help!!

 

[KrisReef]

Feed the fish and the fertilizer is free.

A protein skimmer adds Oxygen to the water an removes waste from the water. A fuge removes nothing, just changes nutrients into plant material

I presume your top-offs are with freshwater, deionized is best. Water changes remove waste like a skimmer. Folks often use nitrate test to determine how much water to change.

Be nice to Old folk. We all become one if we live long enough.

 

[Mical]

Pictures would be a good start. I applaud you for taking on the task, helping older folks is commendable.

To answer what I can from your questions;

A skimmer is not necessary but helpful in filtering out some organics.

10% water changes are better than nothing.

There is no liquid fertilzer that I know of for reef tanks, but it would be good to know what coral, fish are in the tank currently.

As I said pics would be of great help..

 

[ReefNewb82]

I will definitely have pictures tomorrow!

So which would be better for someone starting off? A skimmer or refigium? Would prefer the cheaper method but at the same time maybe one reduces the need for constant water changes as well?
It doesn't have much for fish right now either.

And yes water changes are freshwater with prime conditioner right now. They do not have a reverse osmosis system.

Also it has a starfish, I read online they will actually eat coral?

 

[JumboShrimp]

My vote in your situation is to go with a large skimmer over a refugium, for sure.

 

[Flippers4pups]

I will definitely have pictures tomorrow!

So which would be better for someone starting off? A skimmer or refigium? Would prefer the cheaper method but at the same time maybe one reduces the need for constant water changes as well?
It doesn't have much for fish right now either.

And yes water changes are freshwater with prime conditioner right now. They do not have a reverse osmosis system.

Also it has a starfish, I read online they will actually eat coral?

Water changes need to be of saltwater only, not freshwater! Top off should be only distilled water or RO/DI water. Knowing what the tanks salinity is now is very important. Saltwater made must match the salinity of the tank.

Skimmer is better. Refugium will require a light and macro algae. Skimmer is used for removing proteins in the water which must be removed. Refugium will not do this.

 

[dadnjesse]

Whats wrong with the skimmer? I would try and clean the pump maybe that's all it needs. If the pump won't run you could just replace the pump

 

[Auquanut]

Welcome to R2R! You definitely came to the right place. I applaud your interest in keeping such a large tank functioning. I agree that the skimmer may yet be salvageable. It could be just a matter of cleaning or replacing the pump. If I had to choose one over the other, I would go with the skimmer every time. Please try to provide as much info about the tank as possible and we will do everything we can to help. Pictures of absolutely everything would be awesome.