Population control?

[JBFUK]

Hi all,

I'm very happy to have my 125L planted tank running for a few months. I have a few concerns regarding my Snail and Guppy populations which are growing rapidly and wondered what peoples advice would be regards controlling them.

First the snails, they are spotted ramshorn snails, I added three adults and they do a good job of eating algae that the fish don't take care of. Problem is, in the past week I started seeing some babies and now I suddenly have an explosion of them. I haven't counted but there must easily be 50+ small snails all over the place. What's the best way to control but not completely eliminate them? I was thinking of getting Assasin snails but without having any experience I'm not sure how many I would need, whether I would have a similar population problem with them if I have more than one, etc? Would appreciate some experienced guidance on this.


Second the Guppies. It's really nice to have livebearers, my wife an I both like to see the fry swiming around, we only have one batch of fry at the moment (approx 10 of them) but I can forsee issues with overpopulaton if the 4 females we have keep popping out 10+ babies each every month. I see my options as being:

1) Introduce a predator or predators. My preference would be a pair of golden rams but I would consider a single or pair of angles if the rams would be ineffective at controlling the guppies (particularly while the rams are young). We want some fry to survive but don't want to be over-run. Also have concerns either of these would eradicate the cherry shrimp from the tank, I put two of my cherry shrimp in my 40L tank a few months ago which is home to a single ram. Haven't seen the shrimp since although some baby red shrimp have appeared so perhaps they just went in to hiding.

2) Remove the male guppies. This would be a shame as they are attractive. I also understand the females store sperm so can keep popping out little miracles for up to 6 months without males being present. So this doesn't seem like a good solution.

3) Keep a dedicated tank for the excess guppys and sell them on eBay. Not sure what would be required for heat-sealed brethable bags so that I can safely post them without leaks or deaths if the delivery is delayed for a day or two. Perhaps a lot more hassle than it's worth given how cheap guppies are.


Would really appreciate your input.

Thanks.

 

[sparkyweasel]

2a) Remove the female guppies?
As for the snails, usually a population explosion indicates too much food for them, maybe uneaten fishfood or dead leaves etc.

 

[91]

Option 4. Sell / trade the excess to a LFS. I get £1 a pair fancy guppies, min 25 pairs though not worth it to them for less volume. And £5 per 100 ramshorn snails (puffer food) they will take all i can provide.

Though if you can be bothered there are people buying ramshorn snails at a quid each on ebay.

 

[JBFUK]

2a) Remove the female guppies?
As for the snails, usually a population explosion indicates too much food for them, maybe uneaten fishfood or dead leaves etc.

There was some excess algae but that seems to have cleared up as the tank is settling and the plants are establishing themselves. Will the population level off and reduce based on the environment or will they just start eating the plants? Assassin snails not a good idea?

 

[JBFUK]

Option 4. Sell / trade the excess to a LFS. I get £1 a pair fancy guppies, min 25 pairs though not worth it to them for less volume. And £5 per 100 ramshorn snails (puffer food) they will take all i can provide.

Though if you can be bothered there are people buying ramshorn snails at a quid each on ebay.

That’s a lot of guppies to stockpile before offloading, what size tank do you keep them in?

Doesn’t seem viable to sell the snails for £1 each when you consider the time it’ll take to print labels, go to the post office everyday etc. Nice little business project for kids if you have them.

 

[91]

There was some excess algae but that seems to have cleared up as the tank is settling and the plants are establishing themselves. Will the population level off and reduce based on the environment or will they just start eating the plants? Assassin snails not a good idea?

Good news is they won't start eating healthy plants. They will devour any dying leaves though.
I'm going to suggest your overfeeding and if you want to see them drop off without any work on your part cut down the feeding to twice a week for a month or so. Then you won't get a load of new eggs laid as they will be struggling to feed themselves and will die off to a sustainable amount.

 

[91]

That’s a lot of guppies to stockpile before offloading, what size tank do you keep them in?

Doesn’t seem viable to sell the snails for £1 each when you consider the time it’ll take to print labels, go to the post office everyday etc. Nice little business project for kids if you have them.

It sounds it but watch out if you don't do something quick enough you will have hundereds of little guppies. in no time.
I suggest tetras for population control. Black Widows, adult silvertip sort of size.

Well seeing as for 10 years or more they have paid for 90% of everything aquarium related iv'e purchased except plants they currently have a suite of 3 60*45*45 tanks to grow out in. Usually a 5 pack of frozen food.
The last time i enquired how much store credit i had i walked out with a rio 180 & stand

 

[sparkyweasel]

. Will the population level off and reduce based on the environment or will they just start eating the plants?

Yes, and no. The population will settle down to what the tank can support, - less food = fewer snails. Those ramshorns won't eat healthy plants.

 

[Witcher]

As for the snails, usually a population explosion indicates too much food for them, maybe uneaten fishfood or dead leaves etc.

I'm going to suggest your overfeeding and if you want to see them drop off without any work on your part cut down the feeding to twice a week for a month or so. Then you won't get a load of new eggs laid as they will be struggling to feed themselves and will die off to a sustainable amount.

I see the snails as almost perfectly self-regulating species. Food (debris, dirt, decaying plants etc) = tonnes of snails. No food = tiny population of snails.

Ps. I have tonnes of snails because I'm a little bit lazy with cleaning and I like them, because they do the work I'm supposed to do.

 

[JBFUK]

Thanks for the comments everyone.

Once the fry came along I started feeding a small amount three times a day as I'd read guppies (particularly fry) preferred small feeds several times a day rather than one larger session. I've changed my feeding habit now back to once per day and quite conservative. I did have an accident a couple of weeks ago where I dropped a bunch of catfish pellets in the tank accidentally. Cleaned up as much as I could but I'm sure there were plenty in there that I couldn't get - possible this is what caused the explosion in snails?

On the guppy front it looks like all of the females have dropped their fry now but the overall number of fry visible in the tank seems constant so I suspect the mothers have eaten quite a few. I'll monitor the situation for a month or so and see what happens. I have a spare U3 filter which came with the tank that I could use for a guppy raising tank in the garage if I went down that route. I suppose it wouldn't be planted and won't be on view so no need for it to be fancy or high maintenance like the planted tank.

Interestingly regards my idea of buying some rams to eat the fry I'm not sure that would be effective. I have a single ram in my 40L tank (bullied his mate to death) in which I also have a pair of Campoma Nr.42 Endlers. They had their first batch of fry about a week ago and the ram hasn't eaten any. I also have a bunch of baby mystery shrimp that have appeared in that tank and he hasn't eradicated them either - so not such an aggressive predator after all. I presume even a single angelfish would be significantly more ferocious than the ram?

Just incase you are interested I've attached a photo of the tank, you can see a small army of snails on the left.

 

[sparkyweasel]

I did have an accident a couple of weeks ago where I dropped a bunch of catfish pellets in the tank accidentally. Cleaned up as much as I could but I'm sure there were plenty in there that I couldn't get - possible this is what caused the explosion in snails?

Very possible. And things could have been worse if you didn't have the snails to help you clean up.
The snail population will settle down again over time, reaching a balance with the available food supply.

 

[rubadudbdub]

Option 4. Sell / trade the excess to a LFS. I get £1 a pair fancy guppies

I'd check with your local shops before setting a tank up in the garage to raise the guppies. I wasn't as fortunate as Milla and ended up giving away 70 odd black bar endlers, which were far better quality than the ropey skinny guppies a couple of places had on sale. I considered selling them on aquarist classifieds sites or local Facebook aquarist groups but was too busy for sales in dribs and drabs and needed space back. If freight costs and fish importing becomes more expensive post corona virus, LFS may be more interested in decent locally bred stock.

I separated the females from males and then separated the fry as they became sexable. I started off with 2 pairs, separated males and females within a month and continued to get fry for a few months, not 6.

On the plus side a large population of livebearers made it easy to justify getting more tanks, which have remained even after the endlers have gone.

 

[rubadudbdub]

I also have a pair of Campoma Nr.42 Endlers.
View attachment 149849

These are lovely little fish. Just be aware they'll hybridise with your guppies. Purists would advise keeping them separately to preserve the lineage. I personally wouldn't sell any on as pure campoma 42 as you'll never know if there are hybrid genes in the group now.

Same goes for xiphophorus species.

 

[JBFUK]

These are lovely little fish. Just be aware they'll hybridise with your guppies. Purists would advise keeping them separately to preserve the lineage.

Well that's where I have been smart; I have the campoma in my 40L tank with some Ottos and a RAM - no other guppies or endlers as I agree they are beautiful and I wanted them to remain pure I did have 9 fry, but that's dropped to 7 so suspect the Ram had a snack. Never-mind she'll pop out another batch in a few weeks. I might consider removing all of the guppies from my main tank and replacing with just these once I have sufficient numbers.

So I have been thinking about what to do with my growing school of mixed guppy fry. I'm considering buying a little 34L Fluval Flex for my workshop (they are on sale for £75) to grow the guppy fry from my main tank with a view to either selling them as fry on eBay or possibly selling to my LFS if they are interested. Even if I decided not to do it for long it might be useful to have a small spare tank later for emergencies, quarantine or breeding something else. The thing is I read on a website that your LFS is not allowed to pay for fish even if they wanted to as you need to be a licensed fish supplier to sell to them. I had a google but I can't find much info on this, only on licensing requirements to 'sell pets' which I suppose might count if selling direct to people on eBay but perhaps not if selling to a 'pet shop' as a 'supplier'.

I haven't enquired at the LFS yet but would like to know the law before I do. They seem a bit fussy about things in there. They haven't been selling fish through the lockdown. I called them a while ago as I needed some Ottos to help clean up my 40L tank but they said that they were not allowed to sell fish during the lockdown despite opening half days to sell food/equipment etc. I pointed out that both online shops and PetsAtHome were selling fish but they said that as they are 'licensed' there are specific regulations they have to follow etc etc. I didn't push the point but it sounded like rubbish to me as many of the online shops have physical shops too which must be licensed, and the same for PAH

Was the website I read incorrect?

 

[JBFUK]

Bit of an update for anyone who has a similar issue.

I put my single bolivian ram in the main tank for a few days to see whether he would go for the fry. He wasn't that interested and started bullying the coreys so I took him back out.

After looking at different options I removed all but one of the females and brought a small 35l tank to keep most of the fry in while they develop colours - so I can keep the most interesting ones and then work out what to do with the rest. I also put a blue lobster in there and in addition to being interesting he eats the slow/stupid guppies.

With that still not being enough to keep things under control I finally added two medium sized black lace angelfish to the main tank on Saturday. They have been ferocious and spend all day hunting the guppy fry. I'm hoping that the pair will get a bit smarter and learn to herd the fry towards each other for more effective hunting - will be interesting to see how they develop. The tank is no longer dominated by a cloud of guppy fry with the survivors taking hiding in the vegetation. Overall very happy and would recommend a pair of angels to anyone else who would like to have a population of guppies/endlers but keep things from getting out of control. The are definitely thinking fish and add a lot of interest to the tank.

The angels have been eating or at least showing interest in some of the small cherry shrimp (much easier target than the fry) but seem to be leaving the adults alone which is fine.