Algae outbreak

For balance I am going to show you the dark side of this hobby. I have had an unexplained outbreak of algae. Nutrient levels have never been lower, so I just don't know what the issue is. It could be the salt and I wonder if the fact that all my snails have been eaten by the jade wrasse as exacerbated the problem?

Anyway, I am resolved to rectify this problem & will eliminate potential causes one by one.

One of nevs Frags coming on but look lower....

Fun times with a PAR Meter

I've been playing around with my new Apogee Quantum Sensor (part owned by Gary). Still testing various things but delighted to report that the PAR rating on the substrate is 110.

Using a multimeter means any result is multiplied by 5 to get the PAR reading.

Frag This

Swapped an old powerhead with Nev for some frags.
Frags from Nev (aka Screwloose) are tank bred & therefore tend to be much hardier than frags taken from a wild mother colony.

silver digitata with blue polyps


green plate, with light green polyps


montipora hirsuta


green turbinaria


Blue tip stag...looks like anyway

New Camera

Been playing with the new camera and quite pleased with some of the results

Picture Roll

I've not been on for a while but not been negleting the tank. Couple of new purchases in the summer including a Maxima clam and Cataphyllia. Lost my large Foxface this week which I got from Paul (4head) about a year ago - we recon it had been around a fair few years in total! I'm happy with the look of the tank and the corals are filling out a bit now. I'd like a few more clams to finish off the setup (ahem.....is it ever finished!) and possibly a pair of Manderin's now I have a massive copepod colony. Anyway........ here's some pics which is what you want to see!

Phosphate in Frozen Food

Ever wondered how much phosphate is in frozen food?

Well I have and decided to test for just how much is present.
I may need some input on the maths/calculations but this should illustrate just how much 'free' phosphates are present in gamma frozen fish food.

The experiment

I started the test by measuring out 200ml of RO water - ro water has undetectable phosphate and zero TDS.



Next up the food selection - i like gamma blister packs and so do my fish and corals!


Take four cubes and add to your stock (sounds like a Delia Smith recipe)




Nice looking stock there - drink anyone?



I let this settle and then extracted as clear a sample as possible from the 'stock' and assembled the Hanna checker.


Counting down.....


And the final result is 2.5 ppm of phosphate (maximum reading for Hanna)


I also tested using the seachem kit for comparison. I think this shows its over 3 ppm but not much over!


Analysing the results:

So there is at least 3 ppm of phosphate in 200 ml of water using four cubes. Therefore by defrosting your frozen cubes, you can eliminate the 'free phosphates'. What do you mean 'free phosphates'? Well these are the phosphates that are trapped during the flash freezing process but can be removed by rinsing the food in RO water. Obviously all food contains yet more phosphate but I am not measuring this today!
So how does this effect my tank? Well every time you add four cubes directly to the tank, you are adding phosphate...

Edit: lots of discussion around the benefits of adding the whole cube but I am not convinced the juices contain enough beneficial elements to outweigh the negatives, especially wi the larger prey such as mysis. You can simply defrost your cubes, let them settle and carefully pour away much of the excess liquid or even use a rotifer sieve if you you like!

The maths bit:

200 ml = 3ppm
l litre = 0.6 ppm
500 litre = 0.0012 ppm

Each time you add 4 cubes to a 500 litre system, you increase the phos by 0.001 ppm. Not much to worry about? Yes and no. In just one month (assuming you feed 4 cubes a day) the phosphate levels are set to increase by 0.03 ppm which is almost certainly pushing your tank into unwanted high levels given you are probably already running at 0.03 or higher?
Obviously you can counteract these effects by using phos remover but hopefully I have illustrated its always worth a wash before mealtimes!

Cheers

Adam

Coral Hitchiker

My little urchin decided the torch coral frag would make good camouflage