Questions On Green Spotted Puffers

[CruelCoin]

Hi all, first time post here from Ireland.

I have a few months ago bought 4x Green Spotted Puffers (approx 2cm).

Prior to buying them, i set up and cycled a new 250lt tank for them, at 1.010 specific gravity using redsea salt, loads of vallisneria, java fern, bogwood, slate and a sandy bottom.
I have also collected various shells from the beach, boiled and rinsed them, before scattering around the tank.

When i started, my puffers were bored and glass-surfed, but as i added and added to the tank they now have a pretty complex tank, and no longer glass-surf. (will post pics soon)

Questions i have:

1: filtration: Some sites state using low filtration as they dislike fast water movement, others say over filter as they are messy eaters. Opinions? I have currently a 500l/ph filter in the tank, but have a spare 1500l/ph filter if that would suit better?

2: food: I feed frozen bloodworm twice daily, and twice a week i feed live snails that i breed myself in a separate tank.
Should i feed large snails or small ones that would fit entirely in the mouth?
Is this sufficient, or should i try feeding some seaweed, more snails, different frozen food? I have another spare tank again that i could use to breed daphnia?

3: Water parameters: Some sites say keep juveniles in freshwater. Others say 1.010 as i have. Ranges vary wildly from 1.000 to 1.018. Where should i be sitting on this?

4: As a substrate i have fertilised soil on the bottom, then a layer of river sand, a scattering of river pebbles, and then the aforementioned shells etc.
Is this suitable, or should i replace the river sand with coral sand?

I know this are a lot of questions to ask, but i want to provide the best home i can.

Now, i also know there will be protestations on having 4 of them to a 250lt tank, but i have to balance cost/practicality/visual appeal on this one point.
All other points i will try to maximise for the fish's health.

Cheers for any and all advice,

CC.

 

[Chad]

1. They require good clean water. How you go about that could be a larger filter or it could be more frequent water changes with gravel siphoning. That's really what I recommend. As for flow, I recommend low enough that it doesn't cause difficulty swimming. If it looks as if they are being blown about by it or really fighting it to swim, it's too high.
2. They really need food that will wear down their teeth. Clams on the half shell are great for this, for larger GSP fiddler crabs work, snails of course are excellent. I raised pond snails for my puffers. If you do feed non crunchy items it's best to put them in the crevice of a rock so that when they go to eat they hit their teeth on the rock and thus wear them down.
3. Juveniles can be kept in FW but they quickly get to where they need the salt. GSP can be kept in a wide range, even being able to go full marine, actually reef levels of 1.026. For a true brackish set up I have found they get great color at the higher end. The 1.018 but certainly 1.010 or 1.008 works.
4. No. They are find with river sand. They generally like a soft substrate to sleep on. Crushed coral tends not to be soft enough. A fine grain aragonite sand is good, quite good actually.

As for 4 of them in the same tank...it will depend on sex and how you Aquascape. A juvenile GSP has a very different temperament than an adult. Once they become sexually mature the are pretty aggressive fish and like space...lots of it.

 

[ech0o]

From my general experience, our GSP's have no trouble getting around in the current.  Think about where these fish come from, their body types are certainly no stranger to higher currents, we have medium to high current in our tank running about 12 times our gallons per hour, and a very strong fine air bubble stone that causes even more current, and our GSP's literally swim down into the bubbles and race right to the stone which is no easy feat, controlling themselves effortlessly while hunting down shrimps.
 
Like tcamos says, clams, snails, crabs, there are quite a few hard shelled options. 
 
They can tolerate freshwater very shortly, if even at all.  We have had our GSP's in all water types, and to be honest their colors were best at the higher end of brackish and on into the low end of full marine.  There has even been reports that the some of the largest captive brackish puffers end up raised into their adult lives in full marine tanks.
 
We only keep 2 currently and have them in the high end of brackish right now, trying to grow some plants for them so we brought them back from full marine.  We keep them in a 110L tank and they rarely squabble, but again as tcamos stated, it's all about sex, temperament and aquascape.