Marine Pure Blocks - Are they really necessary?

[Latte]

I've got a FOWLR tank I'm setting up and I could really use some extra space in my sump. I've got two massive marine Pure Blocks at the moment and want to know if it'd be ok to toss them, but a lot of people seem to be all about surface area.

It's a well established tank I've picked up second hand, and it's got a ton of sand and liverock already in it. If I take out the marinepure blocks am I really throwing away THAT much filtration? I don't want to end up with ammonia not able to be broken down because I threw out the blocks.

Keen to hear your thoughts guys!

 

[blaxsun]

I've definitely seen a difference when I remove mine (also have a pair of the large 8x4x4 blocks).

 

[Latte]

I've definitely seen a difference when I remove mine (also have a pair of the large 8x4x4 blocks).

What difference did it make? Not enough bacteria to break down the ammonia? Did it correct soon after or did you need to replace the surface area?

 

[blaxsun]

What difference did it make? Not enough bacteria to break down the ammonia? Did it correct soon after or did you need to replace the surface area?

I took them out to do some sump maintenance and cleaning and inadvertently let them dry out when I got sidetracked. I decided to rinse them off and while they were out of the sump air drying my nitrate levels climbed from the usual 2-3ppm to 10-12ppm.

On replacement my levels went back down to normal within a week, so yes - it did correct in short order.

 

[Latte]

I took them out to do some sump maintenance and cleaning and inadvertently let them dry out when I got sidetracked. I decided to rinse them off and while they were out of the sump air drying my nitrate levels climbed from the usual 2-3ppm to 10-12ppm.

On replacement my levels went back down to normal within a week, so yes - it did correct in short order.

Do you know how the marine Pure Blocks actually lower nitrates? I always assumed it provides surface area for ammonia and nitrate consuming bacteria. I didn't know they then also somehow lowered nitrates too. Do you have much sand/liverock in the tank you removed the marine Pure from?

 

[vetteguy53081]

I use them in my 135 and believe they do reduce nitrate and ammonia . Drawback is . . . as they age, they begin to disintegrate. Those mentioned are about 3 years old. I have new ones on hand

 

[blaxsun]

They're porous and have a lot of surface area, so they're like having a lot of live rock in a very small (lightweight) package. And yes, they do lower nitrates.

 

[MaxTremors]

Do you know how the marine Pure Blocks actually lower nitrates? I always assumed it provides surface area for ammonia and nitrate consuming bacteria. I didn't know they then also somehow lowered nitrates too. Do you have much sand/liverock in the tank you removed the marine Pure from?

They are super porous and the bacteria on the outer layer are aerobic are nitrifying, the bacteria in the center are anaerobic and are denitrifying (they convert nitrate into nitrogen gas, which then gasses off).

If you have lots of live rock, you’d be fine to remove them in terms of processing ammonia, but if your rock isn’t very porous (most dry rock isn’t), you may notice an increase in nitrates. If you have lots of live rock, you might be able to hide them behind the live rock in the display (or you can get the smaller cubes which are easier to hide).

 

[Jbell370]

I use a couple of the large 8x4x4 as well as a couple of the Polyp labs small ones. Planning on adding more since I have the space.

 

[Spieg]

Only one way to tell... take them out and store them in a bucket of water to see what happens.

 

[shakacuz]

they definitely help provide good bacteria with a place to do their work.

my marine pure balls, cubes, and block are slowly disintegrating, as well as being chewed on by my urchin in my sump. looking to get an alternative...polyp lab or eshopps?

 

[McPuff]

I use them in my 135 and believe they do reduce nitrate and ammonia . Drawback is . . . as they age, they begin to disintegrate. Those mentioned are about 3 years old. I have new ones on hand

Definitely. I have cycled through a couple... when they start to get really old and brittle I see if anyone else needs to seed a new tank as it'll basically give them an insta-cycle. Then I replace with a new one. Recently, I removed one that was probably 4 or more years old. I did not replace it though... perhaps I should do that still... I've got 3 in my sump right now for a 300gal.

One thing to remember is to rinse them about once per month. You'll see that quite a bit of dirt/detritus comes out of the surface. In theory this should help to lengthen their usable life span.

 

[Eric Miller]

This media I have in my sump now seems to be alot stronger and works just as good.

 

[Sean Clark]

I have one of the 8x8x4 blocks in all of my systems. Is it necessary? No. I like them and will probably always use them in the future. They are pretty fragile so I try not to handle them too much.

 

[areefer01]

Are they needed, no. That was the original question asked.

The bigger question would be is the system designed properly to handle the bioload. That is different and there are different ways of resolving that. One of which is the bio blocks. As already noted it works similar to rock or substrate by providing a surface area for Mother Nature to do her work. Rock, block, and so on. They are porous like a good quality rock (live, or dry).

I sort of like to keep it real. No, not needed. Tool? Yes.