Newsletter - April 2008

• Editorial
• The Website
• Ask John!
• Favourite Fish

Editorial:

I’m an advocate of ‘maintain and watch.’ What I’m talking about is the marine aquarium, of course. Some aquarists set it up (having a great deal of fun I hope) and then make adjustments.

This is all well and good as it is almost never quite right at the beginning of the aquariums life. Sometimes it is necessary to move a coral or two, and the corals may well have rocks attached. Perhaps the corals were moved as new corals have arrived that need more light or current.
Anyway, no problem with adjustments from time to time.

What the living captive reef wants is stability of the seawater parameters, lighting quality and time. Seawater parameters are easy, routine checks confirm the situation.

Lighting just needs a little maintenance and changes of bulb and/or tubes at the relevant moment. What is time? It is the chance to settle and remain settled without disturbance.

On the wild reef, barring small disasters like storms, there isn’t any over-interference.

My soft coral tank has been running for 5½ years. I do regular maintenance once weekly, so hands are in the tank then. I also have to cut corals from time to time because of overgrowth and crowding. Apart from that, the reef is left alone, though of course it is monitored.

Closely looking at the reef rocks it can be seen that they are covered in marine growths. On the surface is much coralline, though to be truthful there isn’t much surface rock to be seen. In addition are many, many short hard growths that look like sticks, about 1″ long and 1/8″ in diameter. At first I thought they might be tube worms, or the home of some kind of worm, but despite close observation I have not seen any evidence of any type of worm. I’ve tried reference books to no avail. Being honest I’m not bothered as they are clearly not malignant and on close inspection are interesting enough.

On the underside of the rocks, when viewed at night (they can be seen during daylight but don’t seem so clear) are lots of tiny tubeworms. Tubeworms they are as the feathery heads can be seen, not the big showy ones but about ½” or so in diameter, often smaller.

I find these tubeworms in my canister filter as well. There are lots of other growths the identity I’m not sure of. Again, no problem. The rocks are clearly heavily populated.

There is one worm that lives in a tube toward the top of the tank. It was not there when the tank started, but appeared perhaps a year later, or that’s when I noticed the small tube anyway. The tube is now around 2″ long, maybe a little more, and about 3/8″ in diameter. It is definitely a worm, as it can just be seen at the mouth of the tube. It is not a feather duster. What it does to feed itself is trail a very thin sticky thread out in the current. When food becomes attached to the thread it winds it in and consumes it. The worm must think its in aquatic heaven - it gets varied frozen food and flake targeted at the fish.

The worm has been designated ’fisherworm.’ Very technical!

The thing is, I didn’t use any live rock whatsoever when the system started. It was highly porous and inert rock. It was thought, and proved correct, that the import of corals which would be attached to rock would kick off the process of turning the rock live. As said this happened - and is probably partly to do with non-interference. If I were to do this again some live rock would be incorporated, maybe a quarter of the total, and the process would probably be quicker. Anyway, the sulphur denitrator was turned off a good time ago. From system start-up to now there has never been a nitrate reading. The anti-phosphate filter remains running.

The Website:

I hope everyone has had the opportunity to access the new look website. It is a big advance from the previous one, with more colour and user friendliness.

At the moment Peter is engaged in another update. In the very close future when tests are complete, a new feature will appear, this is called ‘Aquarist Online Social.’ This will include the forum, gallery, videos, a chat room etc. I’ve had a preview and it looked good to me even though it wasn’t finished.

Because of the website update the forum cannot at the moment be accessed. This is unfortunate but can’t be avoided. Those who had pending entries have had opinions provided.
All the entries from the old forum will be transferred to the new one.

Anyway, please bear with us. Our apologies for any inconvenience but, as said, in my opinion the wait will be worth it.

Ask John:

Some queries have been selected and shown below as they may be of some interest:

I have a 210 aquarium would a 55 gallon sump be enough?

Saul.

John replied:

Hello Saul. A 55 gallon will be enough, though in general the bigger the better. Any sump increases the amount of water in the system, which is good for water quality. Note that when calculating the fish load, the net gallonage of the display aquarium only is used, to ensure the water in the sump does in fact contribute to quality.

If you are thinking of installing a deep sand bed (DSB) in the sump, then the guideline for the sand bed area is 2/3rds of the display tank base area. This guideline is not always practical, in this case as close as is possible to the guideline should be ok.

John.

Hi John.

I live in southern Colorado, far from the ocean, but am having fun with my new aquarium. Minus the lack of help out here. I have gone to pet stores in neighbouring towns but haven’t gotten much help. My chemical levels are all good, except nitrate. I have done water changes, changed the filter and kept the algae cleaned up, but the nitrate still tests high. My fish are doing well, we’ve lost a couple, but from what I have read it is not uncommon, especially when our stores have the fish shipped in. I have a gravel floor in my tank, and I am wondering if a live sand bed would be better, and if so how do I replace the gravel without risking my fish?

Melvin.

John replied:

Hi Melvin.

Nitrate does raise an obstinate head in some marine systems. The first thing I would suggest is to examine what you are doing.

Feeding. This is often the number one way that nitrate (and phosphate) gets into the tank. Overfeeding is the enemy of water quality. It is easy to overfeed as fish and shrimps ‘beg’ for food and it is oh so tempting to give them some. There is an article called ‘Feeding Time’ on the site, link below:

http://www.aquaristsonline.com/articles

Overstocking. Have you overstocked? If so then you are probably overfeeding too for obvious reasons. You may want to look in Articles for stocking suggestions.

Doing water changes is very good and highly recommended, nitrate or no nitrate. It does take many standard water changes to reduce nitrate significantly, and of course nitrate is being added all the time.

Algae in the tank is feeding on nitrate, and is helping to an extent. However, of course we don’t want the algae. You have a gravel bed - is it clean? Detritus can build up to a considerable extent and this doesn’t help.

Are you using tap water or reverse osmosis water? If tap water, check and see if there is a nitrate presence. If there is, I suggest you use reverse osmosis water. Reverse osmosis is recommended anyway.

A deep sand bed (DSB) is a great addition to a marine system, but must be constructed properly. There is an Article (well, what a surprise!) on the DSB.

If the nitrate problem really cannot be solved, despite all efforts, then nature can assist further. There is a filter called a denitrator. Bacteria colonise the media in these, but are in a very low oxygen environment. Because they need oxygen, and there isn’t enough present, they use the nitrate - they take out oxygen which breaks the nitrate down. There are two main types of denitrator, and the best (in my opinion) is the one based on sulphur. It is quite easy to run and does not require feeding which the other type does.

You say you ‘changed the filter.’ I assume that you are using a canister filter? If so, the filter will produce nitrate as part of the biological support function, and the nitrate will not be naturally removed from your aquarium by this filtration.

Doing one, or some of the above should hopefully solve the problem. I don’t know what your nitrate level is, but the target level in a reef is 10ppm (parts per million) or less. In a fish only, ideally the same, but 30ppm or so is more likely. Some aquarists have tanks at 50ppm. The higher the nitrate (and phosphate) levels, the more likely there will be a problem with nuisance algae.

John.

From Brandon.

I have found your guide to be very informative so far and have 2 quick questions for you. I noticed that you do not recommend that a person use tap water to do partial water changes on a tank. I do not have access to the reverse osmosis filtered water and was wondering what some alternative options might be? Is bottled spring water better than tap water? I have been running my salt water reef aquarium for 2 ½ months now and have been using tap water for all water changes. I use the water conditioner on my tap water at all times to remove the chlorine and other chemicals but am not sure if that is good enough.

Also do you have any additional recommendations on how to decrease nitrate levels? I have 70lbs of live rock and a deep sand bed but my nitrate levels appear to be quite high. I have been doing 2 20% water changes per week to try and reduce this and although it has helped a little, the levels are still high. I also purchased some nitrate sponge chemical filter and placed that in my canister pump and again it has shown little improvement.

Any advice would be appreciated.

Regards,

Brandon.

John replied:

Hello Brandon.

We’re very pleased that the guide you have is proving useful.

Water changes are recommended as part of routine maintenance whether there is a nitrate problem or not. These changes can take more time than expected to show any real improvement, and nitrate is still being produced in the tank of course.

Tap water is not recommended in general as in many areas it contains excessive nitrate, phosphate, insecticides, bacteria, metals etc that are not good for our marine stock.

Some areas however do have very decent tap water, and some aquarists even have a well which contains pretty pure water (tested). Reverse osmosis (R/O) water is normally the way to go, the units can be purchased on the internet at a reasonable price. They are connected to the mains water supply and produce filtered, or purified, water. They come in various ‘gallons per day’ outputs and one of these is selected that can cope with the gallonage used in a routine water change. The water is also used for topping up. R/O is a surer way to go than bottled and the rest.

Before using bottled water, check the water content. This is often printed on the bottle itself, but some companies will respond to an enquiry. It could well be an expensive way to go, and R/O in the medium term is probably going to be cheaper.

As far as nitrate goes, check your feeding regime. Feeding is often overdone and is a prime way to increase nitrate levels. I note that you have live rock - good quality live rock can deal with nitrate within reason. This makes me wonder about overfeeding. You also have a deep sand bed (DSB) which makes me wonder about overfeeding more.

Is your canister filter used for mechanical filtration only? If so, be sure to clean it regularly to prevent excessive detritus build up. If you are using it for additional bio-filtration, note that the canister will be producing nitrate as an end product, This could well overpower the ability of the live rock to deal with it all. The canister, if bio, will also be taking work away from the live rock and may have a detrimental effect on the bacteria populations in the rock. If the canister is bio, try stopping it, but keep a watch on livestock in case the live rock bio filtration is not able to support them. Again, with respect, don’t overfeed.

Nitrate levels can be reduced by the use of a denitrator. This is a filter which uses bacteria, but they are in an oxygen poor environment. To obtain oxygen, the bacteria extract it from nitrate, which breaks the nitrate down. In my opinion, the best denitrators are the ones based on sulphur, as they do not need feeding and are a little more forgiving.

When live rock is in use, coupled to a DSB, there should be no need for a denitrator. As said, check the water you are using, examine the feeding amount (the little gluttons always seem to want more but they most often don’t need it) and hopefully all will improve.

John.

Favourite Fish:

This is the area where favourite aquarium fish are looked at. The intention is not to go into great detail, but just to have a look.

Commonly known as the Dottyback Diadema, or Flashback, this fish is properly called Pseudochromis diadema. It is a lovely little fish that could grow to about 2 ¼” (circa 6cm). The body is coloured yellow, with a purple stripe that runs all the way down the back from the mouth to the tail.

To be settled in the aquarium (it is suited to a reef) there needs to be plenty of hide holes. That’s not a problem of course. The fish is a good eater, taking flake, and many frozen foods commonly used by aquarists. It will also hunt among the rocks for those tiny life forms that can often be seen scuttling about. The fish is hardy and just right with its colour mix to add to the colours of other fish in the display.

Mentioning other fish in the display - there must only be one dottyback as an overall rule, and particularly with this fish. Otherwise there will be war! These fish can be very territorial and aggressive.

This fish on occasion can even be aggressive towards other non-related species, even those bigger than itself. I made sure that the other fish in my system are themselves aggressive and/or well able to take care of themselves. Also, the diadema went in last.

Even so, there were disputes between damsels and the fish, though no harm came of it. Just be aware of the possibilities with the fish. Any doubts, look for another.

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