Starting up a new 75G fish only tank

rydys

New Member
This is my 1st post. So please be nice.

I have had freshwater tanks over the years and now finally saved up enough to do saltwater the right way.
The #1 goal for this tank is that it should look beautiful, colorful, lively and active and be extremely easy to maintain.

I am planning on having a wet/dry with a skimmer and a cannister filter.
I am starting the tank with purchased sea water and 4 bags of sand and 50lbs of rock.
The tank should be delivered next week, after which I will let it sit for 2 weeks to "cycle".
Then slowly add fish.

Any suggestions or comments?
 
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lmforbis

Well-Known Member
Fist skip the canister and wet dry. Both are pricy and Neither are great choices fore a marine aquarium. Since you are planning on a wet dry you can switch to a sump. You can build this yourself from an aquarium (20 gal long or a 10 gallon and either glass or plexiglas dividers siliconed (aquarium safe only) in place or buy a pre made sump. Your skimmer can live in the sump as can other equipment you want to hide like heaters. Add a light and It also provides a place you can grow macro algae which is great for water quality. Alternatively a simple hang on the back filter works well.
You will also need a couple of power heads, around 800 gph one at each end of the tank pointing at each other. You can spen a lot on them or a little. It doesn’t matter. I have the best luck with the cheap ones, they seem to last longer. The ones that attach with magenta are easier to deal with.
You didnt mention heaters. You will need that too. I’d recommend two smaller ones rather than one big one. If something goes wrong with a heater and eventually it does. The issue is less with two smaller ones. You have more time to see the problem.
Your tank size is good for a starter tank just keep in mind you can’t put as many fish in the tank as with fresh water. I’m glad you chose sand over crushed coral. It is a better choice.

Now for the cycling. You will need a good 6 weeks to cycle it before you even consider fish. Then only one fish at a time (unless you are doing a pair of very small clowns. Add them in order of least aggressive to most aggressive (avoid damsels like the plague) Keep in mind marine fish are all very territorial so only one of each kind. You don’t want two that look similar. For example you can have 2 clowns (an exception) if you get them very small if they are the same species but you can’t have two different kinds of clowns. Your tank is too small for most tangs. I’m saying this now because every body wants a tang. The exception would be a yellow tang or one of the bristle tooth tangs.

Next subject quarantine. Most marine fish these days have some sort of parasite. The distributors tanks are generally full of parasites. Often the stores keep their salinity low or run low levels of copper in their tanks to suppress the diseases. Once you get them, bam full blown parasitic disease and now you need to treat all your fish and keep your tank empty for weeks to rid it of the parasite. This can be prevented by setting up a quarantine system consisting of a bare bottom tank, a heater, a sponge filter and some PVC pipes to provide a place for the fish to hide. Cheap, easy to st up and it will save you a ton of money long term and a lot of frustration by keeping the diseases out of your display. I quarantine all fish a minimum of 30 days. If all looks good then I move them. If a disease pops up I treat it in an easy to control environment.
 

rydys

New Member
What is the difference between a wet/dry and a sump? I thought they are the same thing!
I was told that using live sand and natural sea water will cut down on the cycling time!
I forgot to include the wavemaker. Do I also need powerheads if I have a wavemaker?
 

lmforbis

Well-Known Member
A wet dry is focused on aerobic bacteria and tends to cause higher nitrates, same with a canister just worse. A sump allows for all kinds of different filtration options as well as a place to put equipment.

Live sand isn’t going to help much. In reality most of the bacteria in it isn’t alive anymore by the time you get it. I wouldn’t waste the money on it unless it was the only way to get the size of particle you want. Natural seawater contains little bacteria. I assume you are referring to boxed seawater not straight out of the ocean. Never use straight from the ocean. The only thing that really would speed it up is if you were using all live rock, from a local store so it isn’t out of the water more than an hour. In most cases that is cost prohibitive at around $10 or more per pound. It is a good idea to buy one good chunk from a good store that keeps it in an isolated system free of parasites to seed the tank. Cycling takes time. The key to successful saltwater aquariums is patience. That starts with cycling properly and continues for the life of the aquarium. You will need an ammonia, nitrite, and nitrate test kit. Quality ones like those from Redsea, Salifert, NOT API. When you set up the tank you will need a source of ammonia. I like to ghost feed as if I had fish, some add ammonium chloride, some add a raw shrimp. This is the food for the bacteria. This bacteria needs to colonize your rock. The Biological filtration will be happening on (aerobic) and in (anaerobic) that rock, that is your filter. That is why you don’t need a fancy filter. I don’t run a filter at all. I have a sump with macroalgae and some rock rubble. It holds my skimmer. The rock in there does provide more surface area for bacterial growth but that’s it. The macro algae helps keep nitrates down and I harvest it periodically to feed my rabbit fish and tomini tang.

Rule #1 always be patient never rush things.
Rule #2 never listen to the guy at the fish store.
Rule #3 always quarantine
 

rydys

New Member
How does a sump differ from a wet/dry? My question is what does a sump do that a wet/dry doesn't?
If I have a sump with a skimmer in it and a canister, is that better? Or should I forget about the canister altogether?
 

lmforbis

Well-Known Member
Forget the canister. The worst kind of filter for a salt water tank.

A wet dry works by the water flowing over a media like bioballs. They aren’t submerged. The bioballs are coated by bacteria that needs air, aerobic. The end product of the aerobic bacterial breakdown is nitrate. In a wet dry filter there is no way to get rid of the nitrate.

A sump isn’t really a filter. It provides some extra volume which helps with stability, it is place for equipment, a place where you can set up an auto top off system to keep salinity stable. In the sump you can put things that do provide filtration especially temporary like filter socks, or reactors. I don’t like filter socks because they tend to add o nitrate problems and really need to be changed every 1-2 days. Live rock rubble works so does macro algae. Macro algae in a sump with a compact fluorescent bulb will do a great job of using up nitrates and out competing nuisance algae in the main tank. What people have a hard time grasping is you don’t need a filter in a salt water tank if it is set up correctly, they think you need a lot of expensive equipment to be successful. All you need is enough live rock. Dry rock becomes live rock once the bacteria colonizers it. The surface of the rock breaks down the ammonia and nitrites. The inside of the rock can break down nitrates as well as the bottom of the sand bed. A skimmer is nice but not necessary especially in a fish only system. You said you wanted low maintenance. You won’t have that with a wet dry or a canister
 

lmforbis

Well-Known Member
My tank is almost maintainence free. It is a 120 gallon tall tank with a 40 gallon sump. I do a 25% water change every couple weeks and that’s it. This one has been up and going for years. I’ve been doing salt water over 20 years. It is as much work as you make it.
 

beaslbob

Well-Known Member
Whatever you do I recommend you start with macro algae or an algae truf scrubber right from the start.

A sump with a large refugium for the macros is one way.

Another is just to partition the display so there is a small area for macros.

my .02
 

rydys

New Member
Just to make sure that I understand correctly; a wet dry is a sump with a spray bar that trickles water down over a medium such as bio-balls which breaks down nitrites into nitrates. The downside of this is that it generates a large amount of nitrates which can only be removed by water changes?
 

lmforbis

Well-Known Member
Pretty much. You generally can’t put any equipment in a wet dry and it doesn’t provide enough extra volume to be beneficial for stabilizing the water parameters. I have found them to be kind of noisy as well. A sump can be pretty quiet if it is set up right.
 

beaslbob

Well-Known Member
Just to make sure that I understand correctly; a wet dry is a sump with a spray bar that trickles water down over a medium such as bio-balls which breaks down nitrites into nitrates. The downside of this is that it generates a large amount of nitrates which can only be removed by water changes?
almost correct.
Nitrates can be reduced by plant life like macro and other algaes. They also consume co2 and return alk, oxygen, and fish food.

my .02
 

rydys

New Member
So if I understand correctly, a properly cycled tank with healthy levels of bacteria and live rock and live sand, with appropriate levels of algae would not need a water change as there will not be any nitrate build up?
 

beaslbob

Well-Known Member
So if I understand correctly, a properly cycled tank with healthy levels of bacteria and live rock and live sand, with appropriate levels of algae would not need a water change as there will not be any nitrate build up?
That's correct.

Actually you would have to dose calcium, alk, and magnesium for reefs type tank.

But essentially you have it correct.


I go a little further than that in that no bacteria is actually needed. The macro algae will consume ammonia if present before nitrates. then, as bacteria builds up and consume the ammonia, the macros are forced to use nitrates for nitrogen.

The same thing can happen should something go bump in the night (fish death, over feeding or whatever) with the macros stepping up to consume the ammonia bump and preventing a dangerous crash.

But that's pretty nerdy and I hope not too confusing.

Besides
It's just my and my .02
 

lmforbis

Well-Known Member
Wrong, water changes will always be needed. No nitrate is hard to achieve and there are other possible contaminants that can get in your water from the environment.

Water changes are also the way we replenish trace minerals that are important for the life we are taking care of.
 
Just an fyi a sump isnt needed... more and more and more people are learning that protien skimmers and sumps arent needed at all.... For reefkeeping the mentality was always low phosphates and low nitrates.. not true anymore and people are finally getting that.

I had a 55g hexagon.. no sump.. no skimmer.. just a hob for mechanical filtration using a micro pad id clean weekly in the sink.. and for carbon if needed.. i had a few power heads and a little eheim 350 surface skimmer and thats it.. I had 10 fish and 34 corals in that tank and i had 0 coral deaths. The only thing i did do was i made a 3 liter bottle putting all seachem denitrate in it. Hooked up my 80gph surface skimmer to it with tubing.. The flow coning out was 28gph.. Perfect for denitrate.. my nitrates went from 40-50ppm to 30 then 20 then would hover around 10-20 and i nevee had to do huge water changes again.. ever.. and i laugh at people who say water changes are needed for (trace) elements lol... right trace elements using RO DI right.. you know RO DI has no trace elements.. so im curious where are these trace elements coming from ? Because RO DI removed up to 99% of the trace elements.. In fact im betting the tank water has more trace elements in it then the RO DI you used for that water change...

There is a reason discus owners dose trace elements because most of them use RO DI water.. something i guess marine keepers havent caught up with ?

Fyi i use straight city tap water btw.. so i dont even use RO water

I moved that tank to my 135 gallon... its a 38 year old 135g not drilled.. so again no sump no protien skimmer... all i have is two emperor 400s simply because hang on backs are the best for mechanical fiktration and emperors have insane suction on the inlets i like to keep the floating particles to near 0 in my tank.. clean the pads weekly and thats it.

I put my denitrate thing on, while it does slow nitrates it doesnt stop it . But 3 liters isnt enough.. I plan to make a 2nd 3 liter container with a 2nd eheim 350 80gph pump.. So i have two working together to lower nitrates below 40 so i dont have to do watee changes.. I have 100 lbs of sand and 120 lbs of rock in the tank. Besides an ich outbreak that is done.

I have a naso tang. Yellow tang, tomini tang, foxface, 6 green chromis, 4 blue damsels, and a flame hawk. My corals arent in the tank yet they are in my 20g long tank which just has a power head and hang on back.. No corals because im just finishing up hypo. I habe 1000$ in corals in that q9g tank..all LPS SPS leathers.. like acroporas.. 3 bubble corals.. torch fragspawns hammer.. neon nepthea and many more..

But you get my point. Im trying to make here. I have no money invested in equipment besides power heads lights and 60$ on 2 hang on back filters. Some people put too much thought and time into this... I mean think about it all a sump is is just a few extra gallons for water dillution and space for more rock and thats it..

Ive seen people go to extremes by drilling holes in their floors. Plumbing pipes in the basement having a swiming pool and jungle of wires everywhere for a sump on a 200 gallon tank and for what ? What does that do exactly.. besides make your house look like trash and cost money.. nothing. You wanna keep nitrates low ? Make a few homemade canisters with denitrate... nitrate problem solved.. I didnt change water in that 55g tank for 6 months..


Some people online have 400+ gallon tanks.. same thing... nitratws phosphates are super high and no issues in corals or fish..

I setup a 30g tank for my mom.. no sump. Just a hob a power head, 30 or 40 lbs of rock and her fish are doing great.
 
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Wrong, water changes will always be needed. No nitrate is hard to achieve and there are other possible contaminants that can get in your water from the environment.

Water changes are also the way we replenish trace minerals that are important for the life we are taking care of.

Maybe 0 but keeping it level is Easy if you make a homemade denitrate canister with low flow around 20-30gph.. i had one on my 55g hexagon reef.. i had 10 fish in that tank and fed alot... my nitrates went from 40 to 10-20 and i didnt do water changes for 6 months. Ro DI has no trace elements.. Thats the whole point of ro di water lol it removes 99% of everything.. Most people use RO DI ( i dont) and so a water change does nothing to replenish elements. Besides whats in the salt.. But you can do that same thing by dosing trace elements and dosing for corals
 
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