My Diminutive Algae Scrubber

I had my glass aquarium built for me with a few additions inside. At the left end is a small triangular area which contains four pumps and also the intakes for canister filters, an anti-phosphate filter, a denitrator (not now in use), and a protein skimmer.

The skimmer is a hang-on type which fitted except that the outlet, which flows down a flat surface, was not long enough. Anyway, the supplied flat plate outlet wouldn’t go down into the aquarium as the side-strap got in the way.

“Hmm” I thought, engaging super Do It Yourself brain cell.

After doing a few measurements I went to the LFS and had some bits of glass cut to act as barriers to seawater. When these were supplied I siliconed them into place on the side brace on each side of the skimmer outlet and also behind it.

Then I obtained some rigid plastic and cut a piece of the correct length to reach the seawater after bending over the side strap. Easily done, however I was left with a length of straight plastic when I needed a bent one.

A piece of cardboard was obtained and bent to the angle required. Then I got my blow torch out (normally used for plumbing) and carefully heated the plastic at the bend point, with the plastic over the edge of a piece of thin metal. This was the part where I thought the plastic would be ruined. But no, keeping the flame of the burner away from the plastic I managed to bend it correctly. Now it was cup of coffee time – very pleased.

The old plate outlet was cut off leaving only a fairly short flat piece close to the skimmer, and the new plate was then glued to the remaining part. When the glue was fully set, the skimmer was switched on and everything worked, with the returning seawater going into the aquarium silently.

I realized that this run of seawater over the flat plate would be a good air/water interchange and so be useful in ensuring a good oxygen level. The original need though was just to get the seawater back into the aquarium properly and quietly.

The return plate sits close to the bank of fluorescent tubes, and what I hadn’t considered was algae. This began to develop on the plate and I managed to keep the plate clean for quite a while as part of normal maintenance.

I noticed that the algae developing was not the green and hairy stuff but much darker, wiry and short. So I stopped cleaning it to see what developed.

The algae developed all over the slope of the plate and as said was the short dark wiry type often called turf algae. I kept a very close eye on it but it didn’t get out of control. In fact, once it had got to 1/4″ or thereabouts it didn’t get any longer. There wasn’t any die-back either. The alga hasn’t entered the aquarium area at all.

The photo I’ve taken is rather ‘blue’ probably because it was taken directly beneath the fluorescent tubes which include actinic types.

The aquarium has been running for a bit over six years and the skimmer the same. There has never been a problem generated by the algae on the skimmer return plate.

I do seawater tests for nitrate and phosphate, and these are usually done monthly. The tests indicate zero, though of course with hobby test kits it is better to say ‘undetected’ as the kits are not of a scientific standard. The algae on the skimmer outlet plate must be finding nutrients of some sort to survive, so perhaps there is a very low presence of nitrate and/or phosphate. The seawater flow is clearly to its liking and there must be a high oxygen presence.

Algae scrubbers are a well known method of nutrient control. The modern type is the sump which is planted with Caulerpa macro algae. They are bigger than my little algae covered plate!

I never intended to have an ‘algae scrubber’, but have now got one of sorts. It is very small but nevertheless will be doing something towards maintaining seawater quality.

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The Fish Tank Hood – Keep It Cool

There are many aspects in the aquarium which generate heat. There are pumps, heaters and of course the lighting.

The choice of lighting normally determines if you will actually use a hood or not. If you choose to use fluorescent tubes then quite likely you will implement a hood or canopy as they are sometimes known. An aquarium hood may be used with metal halide lighting, however this will probably be determined by the choice of metal halide. If you elect for a pendant type then you may not use a hood, however if you use another type of metal halide then you may choose to use one.

As we all know heat rises and if a hood is chosen then all the heat which is generated by the various aquarium equipment will build up in the hood and therefore could have a detrimental effect on the water temperature. Something we dont want to happen is an increase (or decrease) in water temperature. If the heat builds up in the hood then you will also experience a higher level of water evaporation which could mean fluctuations in salinity plus you could experience an electrical failure due to the elevated heat levels.

The good thing is that it is really easy to rectify.

What you can do (and this is one solution out of many) is install fans into the aquarium hood.

Small fans will suffice and could be installed in both sides of the hood. The fans on the left could be installed to blow cool air from the room into the hood and the fans at the other end installed the other way around so that they are blowing air out of the hood. This way you will get an ever moving flow of cool air through the hood.

There are some people who drill holes in the hood rear or top. Whilst this does remove some of the heat I personally do not believe that this will allow for the heat inside the hood to cool down quick enough – unless the holes are of a large size. I personally believe that there needs to be cool air drawn into the hood.

The ambient temperature of the room also needs to be taken into consideration. If it is a hot day for example then the air surrounding the aquarium will be warm and unless you have invested in an aquarium chiller then probably you are going to struggle to maintain the heat within the aquarium. In these instances if you do not have a chiller it is probably best to remove the top from the hood to allow some of the hot air to escape.

Not always possible though is it as you are not always at home.

Computer fans in my opinion are a good option to use as they are cheap to purchase and easy to install, however there are many other fans which can be used. What you need to look at is how you are going to power them. I suppose an interesting way to do this would be via the use of solar power. This way you could use the lighting as the source of power. When the lights are on the fans are activated and when the lights turn off the fans turn off. Perhaps solar powered fans from a greenhouse could work.

Of course another way would be to just hook them up to the power outlet!

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How To Level An Aquarium Stand

Ensuring that the aquarium is level is important. Sometimes if it is slightly out of level it doesn’t matter as the water surface is often above the lowest part of the aquarium hood, or there is a black band on the aquarium to hide the water surface. If the water level can be seen it needs to be visually correct, and in any case it is best if the stand is level in any circumstance for support.

There are two approaches to levelling, and this depends on the start point of the construction – is the stand being constructed from the start or has the stand been purchased complete.

If the aquarium stand is being constructed, then consideration should be given to the site it is to be used in. Using string or similar, mark accurate lines exactly where the stand will go. Then, using a reasonably long bubble level, lay the level carefully along the string, first along the front edge and then along the end line. (If the level is not as long as the line, use a piece of wood the length of the line and put the level on that. Ensure that the wood is absolutely straight, and not warped at all.) Note in each case if the bubble is exactly in the middle. If it is not, raise the level until it is. A measurement can now be taken of the distance that the level had to be lifted to achieve true horizontal. The same should be done with the side lines.

If the levels of the floor are true, then no problem. If not, then proceed in one of two ways. When constructing the stand, allow the additional measurement to be added to the height of the stand at the necessary end, ensuring that strength and stability are maintained. Properly done, the stand top will be level. Or, second, construct the stand as normal as though the floor was level. Then construct a filler, the thickness of which should be the amount by which the level had to be raised to make it truly horizontal.

The downside of adjusting the stand itself is that if it were to be moved to a new location, then it is not going to be level, and fillers are going to be needed. On this basis, it is best to construct the stand normally, and use fillers as described above. If inserting a filler, make it so that support is given to as much of the stand as possible. It may be necessary, if a floor slopes, to construct a triangular shaped filler.

If the stand is ready built, then use fillers where necessary as described above, after checking with a bubble level in the same way.

Aquariums full of water and rocks are very heavy and need to be stable. This is one of the reasons why the stand is levelled, as well as it being visually correct. Maximum and effective support is required if the floor area is out of true. Hopefully, most floors will be level. A little off topic, make sure that the floor itself is strong enough to support the aquarium. If in any doubt, seek qualified advice.

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