Beginner Sponge Help

[AmberOwl145]

Hi everyone,

I have a ~35 gallon tank that's about a year old with a few seahorses and a Banggai cardinal fish. I am using a 32-watt 24 inch full spectrum "25 000 K" Fluval mid-grade light as I thought it would be good for my macroalgae that I recently added. It

Like a dope, I also bought some sponges without doing enough research because I thought they'd look good in the tank with the seahorses. They just arrived today. I bought a red tree sponge which I thought would be a good hitching post (https://www.live-plants.com/redfinger.htm) and an elephant ear sponge (https://www.live-plants.com/elephantearsponge.htm)

I'm concerned for the following reasons:

1. I didn't realize a LARGER and more well-established tank (10+ years) would be ideal. I can't do anything about the size, but I'm thinking to compensate by adding some Reef Phytoplankton that I have coming Friday morning, as well as keep copapods in the tank (I add them 1x each month) and occasionally stir up the sediment/sand a bit
2. I am worried I have too much light going on. Right now I'm doing the regular day/night cycle that this light above offers. Should I try to keep my lights dimmer now in all cases? Wouldn't that be bad for the macroalgae? I'm reading tons of mixed articles about how the red tree sponge would fare good (OR BAD!) in light, so I can't get a clear idea. Everyone is contracting everyone else about it.
3. The elephant ear sponges seem to prefer shade (can anyone confirm) so I should keep them under the shade of my live rock.
4. I have been reading contradicting posts how some say the sponges, when they die, will nuke my tank with toxins, and others say it won't happen and to relax (lol) so i'm anxious about that impacting the seahorses.

Would anyone be willing to help me separate some truth from fiction so I can calm down!

Thank you so much!

 

[ISpeakForTheSeas]

To answer your questions before giving some general advice for sponges:

1- phyto is a good idea (particularly a phyto like Isochrysis galbana or a blend containing it), and stirring the sand bed/turkey basting detritus off of rocks is a good idea too.

2- dimming the lights would be bad for your macroalgae, yes; with healthy sponges and an herbivorous fish to lend a hand, algae growing on the sponge shouldn't be an issue - healthy sponges, corals, etc. produce chemicals to prevent other things (like algae) from growing on and smothering them; if the sponge isn't in great health, however, algae may start to grow on it - that's where the herbivorous fish comes in. Regardless, some sponges like light, others don't, and some don't seem to care either way.

3- research their natural habitat in the wild and see what they prefer in the wild - that's probably your best bet for keeping them.

4- Sponges absolutely will not release toxins and nuke your tank either while alive or dead. Sponges are known for being nearly impossible to keep right now, so plenty of people have had them die in their in tanks, and I don't think I've even heard of an ammonia spike from it - so this is definitely not a concern.


Now, for some heavy reading/advice:

For keeping sponges, I'd suggest reading through the following threads (and any links to other threads in my posts in them):

Sponge Tank

Does anyone have experience keeping a sponge only aquarium? If so where can I purchase sponges. I've only found a few online.

www.reef2reef.com

How hard/easy to grow sponge?

I want to be able to grow sponge for my angelfish. Could I do it in a tank I grow macro algae. It's very nutrient rich water, it's my molly breeding tank. Macro algae grows well in the tank with no doesing. The mollies keep it prestienly clean of unwanted algae and only nip here and there on the...

www.reef2reef.com

Is This Ball Sponge a Goner?

Hi all! First of all, I know the typical spiel - sponges are nearly impossible to keep and feed. Despite this, at the end of December I decided to try one. I feed phyto daily and blast it with frozen food juices and kick up microfauna in the sand for it but not sure it’s enough. I had it...

www.reef2reef.com

With regards to sponges and toxins:

To preface this, I’m not an expert - I’ve been doing a lot of reading up sponges, but I’m not an expert. So, with that out of the way, I know this is vague and somewhat unhelpful, but it depends on the sponge.

Some sponges are highly toxic, some moderately toxic, some mildly toxic, and some not toxic at all. Generally speaking though, sponges produce toxins to avoid predation and/or parasites, or (like some corals) as a form of chemical warfare to compete for territory. With these toxins, some of them are specifically anti-fish, some anti-echinoderm, some anti-parasite, some anti-coral, etc. As I understand it, some of these toxins are deadly to other marine species, and some just make the sponge taste bad or be less preferred by predators.

To address your actual questions now, though, some sponges constantly put out toxins (I know this one has been demonstrated), I’ve heard but can’t at this moment confirm that some might only put out toxins if disturbed/threatened (as you suggested in your post) and some might only be toxic if eaten (this one I find highly likely, but, again, I can’t confirm it at present), and - as mentioned above - some species aren’t toxic at all, so they don’t put out toxins period.

Whether or not a sponge’s toxins are harmful to fish, corals, etc. is - as I hinted at above - dependent on the toxins produced by the sponge and the quantity produced. To give an idea here, sea cucumber toxins (known as holothurin) are ichthyotoxins, meaning they are primarily toxic to fish. So, if a sea cucumber releases their toxins into a tank at a low dose, the fish in the tank will likely suffer (and possibly die) even though the amount of toxin is small, but other inhabitants will likely be unaffected. At a high dosage, however, these other inhabitants may suffer (and/or die) as well.

So, if a sponge produces fish or coral specific toxins, those may suffer or die even if the amount of toxin produced is small. Similarly, if the toxin produced is not a coral or fish specific toxin but the sponge produces a large amount of it, those might still suffer or die regardless.

I’ve never heard of a fish dying from just swimming by a toxic sponge (I’ve only heard of fish dying from eating highly toxic sponges in a laboratory, force-feeding setting at the moment), so I would assume that sponge toxicity is not a big concern under normal circumstances. If you happen to have a highly toxic (either in potency or quantity) sponge that is not being eaten, however, I suppose it’s possible it could pose some health concerns for your tank’s inhabitants, particularly if you don’t do regular water changes or run carbon.

Now, all of that said, I would guess that, in most circumstances, sponges in our tanks are probably either mildly toxic (probably edible but not preferred as a food) or only seriously toxic when consumed (and most tank inhabitants, being chemically sensitive, would likely know better than to eat highly toxic sponges). So, I would guess that in the overwhelming majority of cases, the sponges in our tanks are essentially perfectly reef safe and harmless (though, much like many soft corals, I suspect they would engage in manageable levels of chemical warfare for space in the tank - in that regard I guess you could argue that they are detrimental to corals). This is just a guess, but - like WheatToast - I’ve never heard of a sponge’s toxins causing issues in a tank.

Also, for anyone who’s interested, only a handful of sponges are really considered toxic to humans - they basically give an itchy, painful, swollen rash when touched (contact dermatitis), usually a few hours to days after the contact is made.

 

[AmberOwl145]

To answer your questions before giving some general advice for sponges:

1- phyto is a good idea (particularly a phyto like Isochrysis galbana or a blend containing it), and stirring the sand bed/turkey basting detritus off of rocks is a good idea too.

2- dimming the lights would be bad for your macroalgae, yes; with healthy sponges and an herbivorous fish to lend a hand, algae growing on the sponge shouldn't be an issue - healthy sponges, corals, etc. produce chemicals to prevent other things (like algae) from growing on and smothering them; if the sponge isn't in great health, however, algae may start to grow on it - that's where the herbivorous fish comes in. Regardless, some sponges like light, others don't, and some don't seem to care either way.

3- research their natural habitat in the wild and see what they prefer in the wild - that's probably your best bet for keeping them.

4- Sponges absolutely will not release toxins and nuke your tank either while alive or dead. Sponges are known for being nearly impossible to keep right now, so plenty of people have had them die in their in tanks, and I don't think I've even heard of an ammonia spike from it - so this is definitely not a concern.


Now, for some heavy reading/advice:

With regards to sponges and toxins:

Thank you so much, appreciate it. I'm on day 2 now and it looks fine, no white spots or change in color. The amount of contradicting information out there is wild. The phytoplankton arrived, and I added some, and will continue to do so 2x a week as per the instructions. I am optimistic!

Cheers