Freshwater vs Saltwater

[Krish]

Just an observation I guess, but isn't it strange that saltwater aquariums seem to have more algae issues than freshwater aquariums do when freshwater aquariums seem to go against all the rules we try to keep in this hobby? A few things that come to mind are:

- Saltwater aquairums have ALOT more flow in them than freshwater tanks do so they have alot more circulation to keep waste in the water column to be filtered out. Typically all a freshwater tank has is a bit of surface aggitation provided by a simple hang on power filter so not much circulation provided in there.

- Powerfilters used in freshwater tanks have their media (this includes carbon, cartridges, filter floss etc) changed once every 6-8 weeks which means trapped waste is allowed to sit in the tank and rott for a long time before being removed when in a saltwater aquarium, filter pads etc are recommended to either be changed or replaced every few days max limiting the chances of elevated nitrate and phosphate levels.

- Freshwater tanks usually employ the use of bio-wheels or wet/dry systems who's end product is nothing but nitrates, but in saltwater applications they are pretty much a big "NO NO" so are hardly ever used.

- Freshwater tanks typically use lighting that are probably considered more condusive to plant growth than a saltwater tank does going by their color spectrum.

- Freshwater tanks are usualy way overstocked compared to saltwater tanks and are cleaned maybe once a month to once ever 2 months compared to the recommended weekly schedule that saltwater tanks are recommended to be cleaned.

- Alot of people use regular tap water with a few conditoners in them which half of the time does nothing to remove nitrates or phophates or even silicates in the water in freshwater aquariums, but in saltwater aquariums we use mainly ro/di water specifically to avoid these things.

- Nowhere in a freshwater tank do you see denitrification taking place (unless I am missing something LOL) so all you have are an accumilation of nitrates over time, but in saltwater aquariums denitrification takes place in many different ways (deep sand bed, liverock etc).

So why is it that you hardly ever see a freshwater tank covered in hair algae or any nuicance algae when less filtration methods are being used, less care is taken to maintain them, nitrates and I'm sure phophates are way off of the charts, but in our saltwater aquariums, the slightest bit of nitrates or phosphates found in the water makes for a nice algae outbreak that is noticeable? This is something that has always baffled me... Not sure what the explainantion is here. All I can come up with is saltwater aquariums use a lot more intense lighting than freshwater tanks do and also quite possibly, algae found in freshwater aquariums are not as aggressive as those found in saltwater aquairums??? Heck if I know LOL!

 

[TheKraken]

Dear Krish,

"So why is it that you hardly ever see a freshwater tank covered in hair algae or any nuisance algae when less filtration methods are being used, less care is taken to maintain them, nitrates and I'm sure phosphates are way off of the charts, but in our saltwater aquariums, the slightest bit of nitrates or phosphates found in the water makes for a nice algae outbreak that is noticeable? This is something that has always baffled me... Not sure what the explainantion is here. All I can come up with is saltwater aquariums use a lot more intense lighting than freshwater tanks do and also quite possibly, algae found in freshwater aquariums are not as aggressive as those found in saltwater aquariums??? Heck if I know LOL!"

It is very easy to get algae in freshwater. Most people tend to photograph and share the stunning samples...

If you look at a reef you have a very low nutrient system (clear water unlike the green/blue in Seattle) so living things are forced to find alternative energy. The sun works so you end up with organisms as their own self contained ecosystems (just add light).

If you look at the typical plant habitat you find... Swamp. There are nutrient poor exceptions (like carnivorous plants that eat flies) but you have a lot of rotting biomass falling on land and into the water (leaves). You also have bears (we all know what they do in the woods) and pollution runoff. Most plants are found in rivers or the shallows of the lake where there is substantial blocking of the sun and a reduced photoperiond.

I am a plant farmer. The idea is to provide all nutrients in excess and limit light. By building biomass the plants are actually stripping nutrients out of the water. I have to dump in nitrate (but never ammonia) and other dry salts or plant growth will stop and the algae will take hold. I sell or compost handfuls of plant material every month. If you increase the light you get to a knives edge of nutrients stability where the plants will crash (run out) or go toxic. The paradigm is to focus on plant growth, not algae elimination.

 

[Airphotog]

I am not sure about some of your statements. My 75 fresh has tons of water movement via an Iwaki md40 and watts of t-5 lighting. If I am not careful I will have a tank plum full of hair and or other nasty algaes. But mine is high tech and I know that you are talking about the average lps kit tank. I think the biggest reason is lack of light...

Brian..

 

[TheKraken]

Krish,

If you would like to meet in the middle we can talk about lagoons and LPS/Softee tanks. Due to the proximity to land (nutrient rich runoff) and slower water circulation some corals like to be a little dirty. There are some coral that thrive in absolutely filthy conditions because they have a reliable source of food other than the sun.

I can gauge the rough nutrient level by looking how my chaeto is doing in the sump. If I run nutrient poor it starts to fade away.

I find that looking at any reef advice comes with a little * at the end:
You must run a skimmer*
Canisters are bad*
Nutrients are evil*
You must spend at least $1k/foot for a reef*

where the * stands "for a full SPS reef". If you are looking at Soft Corals or even Fish Only (Aghast) recommendations can be taken with a big grain of salt.

Notice that I have not posted pictures of my planted or reef or African Cichlid tanks on this site. I am a farmer and just working on helping things grow before I make them look pretty.

 

[Scooterman]

I think the biggest reason is lack of light...

Brian..

And how does natural light come into play here, because I hear different reasons why you should never put a FW tank new a window with lots of natural light?

 

[TheKraken]

I am not sure about some of your statements. My 75 fresh has tons of water movement via an Iwaki md40 and watts of t-5 lighting. If I am not careful I will have a tank plum full of hair and or other nasty algaes. But mine is high tech and I know that you are talking about the average lps kit tank. I think the biggest reason is lack of light...

I kinda like my high tech planted tank in that the plants are growing so fast they literally suck ammonia out of the water. I dose back nitrate which that plants have to work to get nitrite and then ammonia. As long as the nutrients are balanced (not limiting to the point growth stops) the plants grow faster than the algae can take hold.

On a side note it is EXTREMELY easy to get green water in a high tech tank by introducing ammonia. While most do this with a sudden upgrade in the lighting, my choice was a huge dose of pH down. You could see ~1" and cut it with a spoon.

 

[Krish]

I agree on the fact that you can easily get algae in a freshwater tank just as it grows in freshwater lakes, swamps etc, but your average aquarium using a standard all-glass tank with it's combo lighting (probably 40 watts) and a simple hang on filter that does nothing to remove nitrates never really has an algae outbreak that is as noticeable as you get with a saltwater tank which is what I find odd. I have been keeping saltwater aquariums for 7 years now and have had freshwater tanks since I was about 8 and have had MANY MANY of them and never had an algae issue. I actually just took down a 40 gal freshwater angelfish tank just before Christmas that I cleaned once a month (5 gal water change) and let the filter pads go about 8 weeks before changing and no algae issues. I try that with a saltwater tank and it would be a different story LOL! All I can sum it up to is the limited light.

In any event, was just tossing out all of this as it runs across my mind from time to time how different freshwater and saltwater aquariums are. What are "no no's" in one is the way to go in another LOL!

 

[reedman]

are we talking about FW planted tanks or FW fish tanks? Big big difference. IME the FW fish only ones are very forgiving as they have relatively low light and the there are fish that like to "eat" the algae. Plus it was easier to just change the water with fresh water. In my area the water out of the tap is near zero TDS so it's not an issue.

Now my planted FW tank grew algae much better than my reef. It had HO lights and plenty of CO2 to encourage plant growth which is also the perfect environment for algae. The key is to have the plants outcompete the algae. You will see this stated over and over in the planted tank forums where they say to add a LOT of plants to start the tank so that they do out compete the algae.

Different systems different challenges.

 

[dtd87]

And how does natural light come into play here, because I hear different reasons why you should never put a FW tank new a window with lots of natural light?

So true, I had friend with a 90 gal Discus tank and he moved his tank infront of his windows and ended up with black bush algae and a freshwater form of cyano. It was a nightmare. He had one of the best eheim canisters a nice 6bulb t5. The sunlight just helped the algae get out of control. He had to move the tank again another 2 weeks later.

As for maintenance I had my 56gallon I would do a 10gallon weekly water change with distilled water, vacuum up all of the debris on the substrate on the bottom and clean out the filters. I've known more people who do more water changes and maintenance on freshwater than salt.

 

[Krish]

Reed, I was referring to freshwater fish tanks. I've never kept a freshwater planted tanks so that may be a different story. With that said, I think we need to "ween" some of these freshwater fish into our saltwater tanks to clean up for us then because they sure do one heck of a job keeping a tank clean if algae is growing in there! The most I've ever seen in any of my freshwater fish only tanks is a slight discoloration on the ornamental rocks and ( **whispers** fake plants :lol: ). Nothing at all compared to algae outbreaks like you see in the picture on the home page of Mojo's article on phosphates. Might be interesting to try a fish only tank with limited lighting like the 40w that come in standard all-glass hoods. I wonder if that would make all the difference...

 

[user 26995]

This can be a controversial subject.....you did this on purpose, didn't you!
I have found the freshwater tanks to be more work than the saltwater tanks. I have planted FW tanks, very low tech, but flourishing plants w/low light. I am doing a water change every 7-10 days on the freshwater with RO/DI water. Filters get changed every 5-7 days. I have extra flow by means of koralia nanos on both FW tanks too.

I dont do nearly the amount of water changes on the SW tanks as I do the FW tanks.

I agree that it must be the lighting.
Although I did have some algae build up on the rock in one of my tanks. I added a BN Pleco and he took care of it in a day or two.

Isnt it suggested with algae growth in the SW tanks to shorten the lighting period? or turn it off completely for days. Thats got to be it. Just the lighting.

 

[mojoreef]

Theirs Freshwater tank?? with real fish??

 

[Airphotog]

Theirs Freshwater tank?? with real fish??

Sorry Mojo that you had to find out this way but yes there are freswater tanks with real fish

 

[user 26995]

Theirs Freshwater tank?? with real fish??

Just think what you have been missing out on! I can help you with that!

 

[Krish]

This can be a controversial subject.....you did this on purpose, didn't you!
.

Actually...Kinda YES!! :lol: Just trying to spark some discussion here and this was something that always crossed my mind. My buddy kept freshwater planted tanks and they were a bit of work from what I had seen. The good I saw though was the fish waste actually worked for him providing food for his plants to grow. Freshwater fish only tanks though, my 4 year old could handle I think it narrows down to the lighting though...Has to be. All of the excess nutrients are there for the algae to make use of and I think it is just the intense lighting that is lacking.

Anyways for Mojo's birthday I think we'll all pitch in and buy him a freshwater setup. Let him experience the darkside for a bit :lol:

 

[user 26995]

Anyways for Mojo's birthday I think we'll all pitch in and buy him a freshwater setup. Let him experience the darkside for a bit :lol:

I've got just the one to start with.

 

[TheKraken]

Anyways for Mojo's birthday I think we'll all pitch in and buy him a freshwater setup. Let him experience the darkside for a bit :lol:

He would just get a bass. Sure it is coldwater and they crap a storm but they like crickets on a string and will chase stuff.

scolley's 75g Big Clear Kahuna (56K warning) - Page 23

I am sure Krish is just trolling us "Why can I keep a mor in a fish bowl? The goldfish is happy."

 

[WABlonde]

Ahh.. great discussion. We had quite a bit of algae going on in our FW. Had a pleco thinking it would take care of it. Pleco got large quite quickly but really seemed lazy. Moved him and bought a baby albino pleco and WHALLA! no more algae. I generally do a 15-30% water change weekly.. or maybe every two weeks when I'm lazy. The filters usually always need replacing by then. I've got mondo goldfish and he's a real pig. Lights are on from 7:00 a.m. until I go to bed.

SW. We have quite a healthly atmosphere for algae.

And we use a canister filter. :flame:We really don't clean it out as much as people say we should but really don't have any issues as far as nitrates/ammonia.

 

[Holidayz]

I've kept FW tank for over 20 years, and sure it can get nasty algae problems just like any other SW tanks.
Believe the major difference is whether it is a fish only tank or planted tank with high lights.
When keeping a high tech planted tank, or make it worse, lets say along with discus, the amount of work Will be no less than keeping a reef tank, if not more.
Enough have been said about keeping nutrients and phosphate level low, and have the plant out pace the algae grow etc. Another key issue is to keep the CO2 level consistent. Some algae, esp brown algae, are very sensitive to CO2 level and can easily break out and cover everything in the tank if the CO2 level is inconsistent, even for just a few days. This would compare to careful calcium/magnesium/alkalinity dosing in a reef tank I guess? All in all, high tech FW might cost less, but amount of work may even exceed a reef tank.
Haha, just sharing my FW experience, new to salt water!

 

[user 26995]

Bushynose/bristlenose plecos are the absolute best for algae control. I bred a pair for a while. Still have two babies left. Sold the breeding pair.