Thinking Of Going From Freshwater To Saltwater

Hello Saltwater Gurus!

Needed advice - I am thinking about going from Freshwater setup to Saltwater on my 75 gallon tank. I have 2 filters - HoB & Canister (no sump or holes drilled). My tap water which I use to fill the tank has nitrates (10-20 ppm).

I have been in freshwater for about an year now and wanted to get a sense of what it would mean to convert the tank. Few questions
a. Does it have to be a sump setup?
b. If sump is absolutely needed would it need holes drilled or hang on back overflow works?
c. With tap water containing nitrates does it mean saltwater is not good (my understanding is sw setup needs near 0 nitrates)
d. Any other advice / tips / suggestions?

I would be looking at live rock no corals to start with and then maybe add corals few months later.

Thanks!

 

A. you don't NEED one but they do help, they hide all the extra stuff like heaters and what not.
B. doing overflow boxes can be trickey but I've never done one, so i'd rather not answer that.
C. You really don't wanna do tap because the city puts a lot of in the water to treat it. Nitrates isn't a big problem as there are millions of ways to export them. The big thing is your TDS in your water, the way to test that is with a TDS meter. For example my TDS from my tap is around 600 then after my ro unit it's around 3-4 then after the DI resin it's 0-1 depending on if it needs to be changed. Honestly amazon has a bunch of rodI units on the low end of the $$$ spectrum so you can use those. Tap water is a no go if you want a reef, you could maybe possibly doubtfully get away with it for a fish only tank, but I'll let someone else chime in on that.

But that's my .02

stella1979 Culprit are pretty awesome in our little salty community.

 

Hello Saltwater Gurus!

Needed advice - I am thinking about going from Freshwater setup to Saltwater on my 75 gallon tank. I have 2 filters - HoB & Canister (no sump or holes drilled). My tap water which I use to fill the tank has nitrates (10-20 ppm).

I have been in freshwater for about an year now and wanted to get a sense of what it would mean to convert the tank. Few questions
a. Does it have to be a sump setup?
b. If sump is absolutely needed would it need holes drilled or hang on back overflow works?
c. With tap water containing nitrates does it mean saltwater is not good (my understanding is sw setup needs near 0 nitrates)
d. Any other advice / tips / suggestions?

I would be looking at live rock no corals to start with and then maybe add corals few months later.

Thanks!

Some good advice was given above. On a 75 gallon you could get away with HOB, but drilled with a sump is the best (Overflow boxes can be a pain). If you do go HOB, make sure it's something like a Fluval 110 or Seachem Tidal 110 and that it is capable of handling a variety of media bags and then getting a solid HOB Protein Skimmer to run as well.
The Eshoppes PSK-100H and the Reef Octopus Classic 100 would arguably be your best choices. Canister filters are the most labor intensive and problematic mechanical filtration method in a saltwater tank, so I don't recommend them. It's very easy for nasties to get built up in them and cause nitrate problems for you. The problem with tap water isn't just the nitrates it's the amount and what kind of solids/minerals/metals are in your tapwater. Unless you live in a rural area with near pristine water it's just too much of a gamble IMHO. RODI ensures that all potential solids/minerals/metals are stripped out. When you consider the cost of an RODI system compared to the long term investment of a saltwater tank it really doesn't make sense to skimp on one and go with a water source that is potentially going to give you out of control algae problems or kill your corals and inverts (and possibly fish). People have also had examples of municipal tap water flushes where levels spike and they weren't aware of it and it killed everything in their tank.

As for live rock, you can go with regular live rock which has lots of biodiversity and bacteria, but it is pricey and also comes with a risk of pests (ie Aiptasia 'nems, Xanthid Crabs, Mantis Shrimps, Fire/Bobbit worms, etc.). They can also be loaded with unsightly bristleworms. Dry Rock lacks any life of any kind, but over time healthy bacteria can be established (but it takes longer) and it would be pest free and is much cheaper to buy. Some like myself chose to compromise and go with Man Made Life Rock (Dry Rock with a live bacteria coating). You might get a few featherduster tube worms (harmless and actually beneficial) but that's about it.

 

Agreed with Soul and Jester. Just wanted to chime in so I can be subscribed to this thread. Let us know if you have other questions.

 

Thanks guys! These are helpful details!
RODI and sump seem to be the way to go, I need to figure out how to drill my tank without killing it. Couple of more questions - any links on what and how to setup sump ? and with RODI water, is it just mixing salt in it and adding to the tank or there are additives that would be needed?
I need a lot of catching up (reading) to understand what I am really getting into !

 

Couldn't tell you how to drill a tank, though it can be done. Lots and lots of research, measure twice, drill once and all that.

RODI water + a good marine salt is all you need to get started. Instant Ocean and RedSea are both good brands for salt. Related to this... you'll find lots of additives you could use, but don't be tricked. My rule of thumb is not to add anything I'm not testing for and that's worked out well for me. In your research, you may find info related to dosing reef tanks but this is not something to concern yourself with until and unless you add corals.

Also, great info above about rocks. FYI, never did a chunk of live rock enter my tank. Dry only for me, and yes, it did take a little longer for things like copepods and coralline to show up, but I'm a patient person and would rather wait for that stuff than deal with pests.

 

Thanks guys! These are helpful details!
RODI and sump seem to be the way to go, I need to figure out how to drill my tank without killing it. Couple of more questions - any links on what and how to setup sump ? and with RODI water, is it just mixing salt in it and adding to the tank or there are additives that would be needed?
I need a lot of catching up (reading) to understand what I am really getting into !

Make sure above all that the glass isn't tempered before you drill, or you will end up with a shattered mess where your tank used to be. As for setting up a sump, a basic setup includes: the overflow in the main tank (where the water drains into the sump and comes back into the tank). It drains down into the sump either directly or into a filter sock. There is debate on the use of filter socks, and you need to be prepared to change them about twice a week if you don't want the nasties to build up. They are washable and reusable and can easily be washed in your clothes washer with tap water and a cap full of bleach and then make sure to give it a few days to dry completely. After the filter sock it goes to the protein skimmer and then the return pump that sends the water back up to the display tank. Some people add a refugium partition to their sumps for things like cheato (macro algae that feeds on nitrates) and copepods (eat excess foods and nutrients in the tank). If you want an idea of what a basic sump looks like, I have a video here showing it in action. Just fast forward to about the 4:45 mark on the video and it will show it:

 

Thanks guys! This has been super helpful. Typically with my freshwater setup I was able to keep my nitrates to a point where I would regularly clean the tank and change the water (30-50%) every 6-8 days. I was close to fully stocked on my 75 gallon and with limited plants keeping nitrates below 20ppm required that work.
With saltwater what is the usual water change needed with sump (including refugium) - I understand it would also depend on the stocking and feeding. Too many questions

 

I usually change 9-12 gallons on my 40 gallon tank.

 

I change 20% per week on my medium stocked reef tank, with a smallish HOB refugium. On a reef tank, with maximum nutrient reduction, along with dosing for minerals and trace elements, means water changes can be few and far between... However, I find it easier to stick with just a refugium, water changes, (which takes care of trace element replacement) and dosing 2-part only (calcium & alkalinity, with a rare magnesium dose)... instead of a larger fuge, high maintenance mechanical filtration, (think filter socks), a skimmer, a reactor for keeping phosphates down, along with the need for dosing trace elements.

Yes, the nutrient & mineral control/water change situation can be as simple or demanding as you want it to be, like so many other things with reef tanks.

 

Thanks guys! This has been super helpful. Typically with my freshwater setup I was able to keep my nitrates to a point where I would regularly clean the tank and change the water (30-50%) every 6-8 days. I was close to fully stocked on my 75 gallon and with limited plants keeping nitrates below 20ppm required that work.
With saltwater what is the usual water change needed with sump (including refugium) - I understand it would also depend on the stocking and feeding. Too many questions

I change 10 gallons per week on my 90 gallon tank with a 29 gallon sump. It's good that you are already groomed for weekly water changes as that will make that a non-factor. For many freshies converting over to the salty side the frequency of water changes is an adjustment.